diff --git a/src/components/Calendar/Calendar.tsx b/src/components/Calendar/Calendar.tsx
index 43df2ec..519d74c 100644
--- a/src/components/Calendar/Calendar.tsx
+++ b/src/components/Calendar/Calendar.tsx
@@ -1,62 +1,111 @@
-import { useState } from "react";
 import CalendarHeader from "./CalendarHeader";
 import CalendarWeekdays from "./Weekdays";
 import CalendarGrid from "./CalendarGrid";
 import CalendarModal from "./CalendarModal";
+import { useState } from "react";
+import type { ScheduleForCalendar, GetDailySchedulesResponse, DailySchedule } from "../../types/calender"; // Import new types
+import { getDailySchedules } from "../../services/calendar.service"; // Import new service
+import { AxiosError } from "axios"; // Import AxiosError
 
-type CalendarProps = {
-  schedulesByDate: Record<string, { id: string; title: string }[]>;
-  onSelect?: (date: Date) => void;
-};
 
-export default function Calendar({ schedulesByDate, onSelect = () => {} }: CalendarProps ) {
-  const today = new Date();
-  const [year, setYear] = useState(today.getFullYear());
-  const [month, setMonth] = useState(today.getMonth());
+interface CalendarProps {
+  schedulesByDate: Record<string, ScheduleForCalendar[]>;
+  onSelect: (date: Date) => void;
+  currentYear: number;
+  currentMonth: number; // Now 0-indexed
+  setCurrentMonth: (month: number) => void;
+  setCurrentYear: (year: number) => void;
+  studyId: string; // New prop for studyId
+}
 
+export default function Calendar({
+  schedulesByDate,
+  onSelect,
+  currentYear,
+  currentMonth,
+  setCurrentMonth,
+  setCurrentYear,
+  studyId, // Accept studyId
+}: CalendarProps ) {
   const [selectedDate, setSelectedDate] = useState<Date | null>(null);
   const [modalOpen, setModalOpen] = useState(false);
+  const [dailySchedules, setDailySchedules] = useState<DailySchedule[]>([]); // State for daily schedules
+  const [dailySchedulesLoading, setDailySchedulesLoading] = useState(false); // Loading state for daily schedules
+  const [dailySchedulesError, setDailySchedulesError] = useState<string | null>(null); // Error state for daily schedules
 
   const handlePrev = () => {
-    if (month === 0) {
-      setYear((y) => y - 1);
-      setMonth(11);
+    if (currentMonth === 0) { // 0월 (January) -> 이전 해 11월 (December)
+      setCurrentYear((y) => y - 1);
+      setCurrentMonth(11);
     } else {
-      setMonth((m) => m - 1);
+      setCurrentMonth((m) => m - 1);
     }
   };
 
   const handleNext = () => {
-    if (month === 11) {
-      setYear((y) => y + 1);
-      setMonth(0);
-    } else {
-      setMonth((m) => m + 1);
+    if (currentMonth === 11) { // 11월 (December) -> 다음 해 0월 (January)
+      setCurrentYear((y) => y + 1);
+      setCurrentMonth(0);
+    }
+    else {
+      setCurrentMonth((m) => m + 1);
     }
   };
 
-  const handleDateSelect = (date: Date) => {
+  const handleDateSelect = async (date: Date) => {
     setSelectedDate(date);
     setModalOpen(true);
-    onSelect(date);
+    onSelect(date); // Call parent's onSelect
+
+    // Fetch daily schedules
+    setDailySchedulesLoading(true);
+    setDailySchedulesError(null);
+    try {
+      const formattedDate = date.toISOString().split("T")[0]; // YYYY-MM-DD
+      const response = await getDailySchedules(studyId, formattedDate);
+      // Frontend should limit to 3 schedules
+      setDailySchedules(response.schedules.slice(0, 3));
+    } catch (error) {
+      console.error("일별 일정 조회 실패:", error);
+      if (error instanceof AxiosError) {
+        setDailySchedulesError(error.response?.data?.message || "일별 일정을 불러오는 중 오류가 발생했습니다.");
+      } else {
+        setDailySchedulesError("일별 일정을 불러오는 중 알 수 없는 오류가 발생했습니다.");
+      }
+      setDailySchedules([]); // Clear schedules on error
+    } finally {
+      setDailySchedulesLoading(false);
+    }
   };
 
-  // 일정 불러오기
-  const selectedKey = selectedDate
-    ? selectedDate.toISOString().split("T")[0]
-    : "";
-  const selectedSchedules = schedulesByDate[selectedKey] || [];
+  // No longer needed here as data is fetched on date select
+  // const selectedKey = selectedDate
+  //   ? selectedDate.toISOString().split("T")[0]
+  //   : "";
+  // const selectedSchedules = schedulesByDate[selectedKey] || []; // This now comes from dailySchedules
 
   return (
     <div className="w-full flex flex-col gap-2 border-b-[1.5px] border-main4">
-      <CalendarHeader year={year} month={month} onPrev={handlePrev} onNext={handleNext} />
+      <CalendarHeader
+        year={currentYear}
+        month={currentMonth} // Pass 0-indexed month
+        onPrev={handlePrev}
+        onNext={handleNext}
+      />
       <CalendarWeekdays />
-      <CalendarGrid year={year} month={month} schedulesByDate={schedulesByDate} onSelect={handleDateSelect} />
+      <CalendarGrid
+        year={currentYear}
+        month={currentMonth} // Pass 0-indexed month
+        schedulesByDate={schedulesByDate} // This is for day cell markers
+        onSelect={handleDateSelect}
+      />
 
       <CalendarModal
         open={modalOpen}
         date={selectedDate}
-        schedules={selectedSchedules}
+        schedules={dailySchedules} // Pass fetched daily schedules
+        loading={dailySchedulesLoading} // Pass loading state
+        error={dailySchedulesError} // Pass error state
         onClose={() => setModalOpen(false)}
       />
     </div>
diff --git a/src/components/Calendar/CalendarModal.tsx b/src/components/Calendar/CalendarModal.tsx
index 08be4ee..0d70241 100644
--- a/src/components/Calendar/CalendarModal.tsx
+++ b/src/components/Calendar/CalendarModal.tsx
@@ -1,9 +1,11 @@
-// src/components/Calendar/CalendarScheduleModal.tsx
+import type { DailySchedule } from "../../types/calender";
 
-interface CalendarScheduleModalProps {
+interface CalendarModalProps {
   open: boolean;
   date: Date | null;
-  schedules?: { id: string; title: string }[];
+  schedules: DailySchedule[]; // Updated to DailySchedule[]
+  loading: boolean; // Added loading prop
+  error: string | null; // Added error prop
   onClose: () => void;
 }
 
@@ -11,15 +13,49 @@ export default function CalendarModal({
   open,
   date,
   schedules = [],
+  loading,
+  error,
   onClose,
-}: CalendarScheduleModalProps) {
-  if (!open || !date) return null;
+}: CalendarModalProps) {
+  if (!open) return null; // Only check 'open', allow date to be null for initial render safety
 
-  const handleClose = () => onClose();
+  const handleClose = () => {
+    onClose();
+  };
 
-  const dateLabel = `${date.getFullYear()}년 ${date.getMonth() + 1}월 ${date.getDate()}일`;
+  const dateLabel = date ? `${date.getFullYear()}년 ${date.getMonth() + 1}월 ${date.getDate()}일` : '';
+
+  let content;
+
+  if (loading) {
+    content = <p className="text-sm text-gray4 text-center">일정 로딩 중...</p>;
+  } else if (error) {
+    content = <p className="text-sm text-red-500 text-center">{error}</p>;
+  } else if (schedules.length === 0) {
+    content = <p className="text-sm text-gray4 text-center">일정이 없습니다.</p>;
+  } else {
+    content = (
+      <ul className="w-full flex flex-col gap-2">
+        {schedules.map((s, index) => {
+          // Extract HH:mm from "YYYY M DD HH:mm"
+          const timeMatch = s.scheduleTime ? s.scheduleTime.match(/(\d{1,2}:\d{2})/) : null;
+          const displayTime = timeMatch ? timeMatch[1] : '';
+
+          return (
+            <li
+              key={`${s.title}-${index}`} // Use a combination for key as no unique ID for schedule item
+              className="flex items-center justify-between text-sm text-gray-800 bg-gray-100 px-2 py-1 rounded-[6px]"
+            >
+              <span className="text-left text-point w-1/4">{displayTime}</span>
+              <span className="text-center flex-1 truncate">{s.title}</span>
+              <span className="w-1/4"></span> {/* Placeholder for alignment */}
+            </li>
+          );
+        })}
+      </ul>
+    );
+  }
 
-  const hasSchedule = schedules.length > 0;
 
   return (
     <>
@@ -46,20 +82,7 @@ export default function CalendarModal({
 
         {/* 내용 */}
         <div className="flex flex-col items-center justify-center gap-2 flex-1">
-          {hasSchedule ? (
-            <ul className="w-full flex flex-col gap-2">
-              {schedules.map((s) => (
-                <li
-                  key={s.id}
-                  className="text-sm text-gray-800 bg-gray-100 px-2 py-1 rounded-[6px]"
-                >
-                  {s.title}
-                </li>
-              ))}
-            </ul>
-          ) : (
-            <p className="text-sm text-gray4 text-center">일정이 없습니다.</p>
-          )}
+          {content}
         </div>
 
         {/* 확인 버튼 */}
diff --git a/src/components/CreateScheduleToDo/DeadlineSelector.tsx b/src/components/CreateScheduleToDo/DeadlineSelector.tsx
index d1e7552..c39a9f2 100644
--- a/src/components/CreateScheduleToDo/DeadlineSelector.tsx
+++ b/src/components/CreateScheduleToDo/DeadlineSelector.tsx
@@ -1,21 +1,52 @@
 import NumberInputBox from './NumberInputBox';
+import React from 'react'; // Import React for React.ChangeEvent
+
+interface DeadlineSelectorProps {
+    month: number | string;
+    setMonth: React.Dispatch<React.SetStateAction<number | string>>;
+    day: number | string;
+    setDay: React.Dispatch<React.SetStateAction<number | string>>;
+    hour: number | string;
+    setHour: React.Dispatch<React.SetStateAction<number | string>>;
+    minute: number | string;
+    setMinute: React.Dispatch<React.SetStateAction<number | string>>;
+}
+
+export default function DeadlineSelector({
+    month, setMonth,
+    day, setDay,
+    hour, setHour,
+    minute, setMinute,
+}: DeadlineSelectorProps) {
+
+    const handleMonthChange = (e: React.ChangeEvent<HTMLInputElement>) => {
+        setMonth(e.target.value);
+    };
+    const handleDayChange = (e: React.ChangeEvent<HTMLInputElement>) => {
+        setDay(e.target.value);
+    };
+    const handleHourChange = (e: React.ChangeEvent<HTMLInputElement>) => {
+        setHour(e.target.value);
+    };
+    const handleMinuteChange = (e: React.ChangeEvent<HTMLInputElement>) => {
+        setMinute(e.target.value);
+    };
 
-export default function DeadlineSelector() {
     return (
         <div className="flex flex-col gap-3 px-4 pt-5">
             <label className="text-[16px] font-semibold text-black1">
                 완료 기한
             </label>
             <div className="flex items-center pb-4 border-b-[1.5px] border-main4 gap-2 text-[14px] font-medium text-black1">
-                <NumberInputBox />
+                <NumberInputBox value={month} onChange={handleMonthChange} />
                 <span>월</span>
-                <NumberInputBox />
+                <NumberInputBox value={day} onChange={handleDayChange} />
                 <span>일</span>
                 <div className="w-1" />
                 <div className="flex items-center gap-[12.5px]">
-                    <NumberInputBox />
+                    <NumberInputBox value={hour} onChange={handleHourChange} />
                     <span>:</span>
-                    <NumberInputBox />
+                    <NumberInputBox value={minute} onChange={handleMinuteChange} />
                 </div>
                 <span>까지</span>
             </div>
diff --git a/src/components/MemberHeader.tsx b/src/components/MemberHeader.tsx
index b4fcb73..07e665e 100644
--- a/src/components/MemberHeader.tsx
+++ b/src/components/MemberHeader.tsx
@@ -1,4 +1,3 @@
-import { useNavigate } from "react-router-dom";
 import type { Member } from "../types/member";
 import Right from "../assets/right.svg?react";
 
@@ -6,15 +5,15 @@ interface MemberHeaderProps {
     members: Member[];               // 전체 멤버 리스트
     currentMembers: number;          // 현재 인원
     totalMembers: number;            // 전체 인원
+    onViewAllClick: () => void;      // "전체보기" 클릭 시 호출될 콜백 함수
 }
 
-export default function GroupMemberButton({
+export default function MemberHeader({
     members,
     currentMembers,
     totalMembers,
+    onViewAllClick,
 }: MemberHeaderProps) {
-    const navigate = useNavigate();
-
     const displayMembers = members.slice(0, 3);
 
     return (
@@ -36,7 +35,7 @@ export default function GroupMemberButton({
                 </div>
             </div>
             <button
-                onClick={() => navigate("/Member")} className="text-[14px] text-point font-medium flex items-center">
+                onClick={onViewAllClick} className="text-[14px] text-point font-medium flex items-center">
                 전체보기
                 <Right />
             </button>
diff --git a/src/components/TodoList.tsx b/src/components/TodoList.tsx
index 2a633f2..3ddf314 100644
--- a/src/components/TodoList.tsx
+++ b/src/components/TodoList.tsx
@@ -1,24 +1,46 @@
 import TodoItem from "./ToDoItem";
-import { todoGroups } from "../mock/scheduleTodoData";
+// import { todoGroups } from "../mock/scheduleTodoData"; // Remove mock data import
 import { useNavigate } from "react-router-dom";
 import Plus from "../assets/plus.svg?react";
+import type { TodoGroup } from "../types/todo"; // Import TodoGroup type
 
+// Add a type for the component props
+interface TodoListProps {
+  studyId: string;
+  isLeader: boolean;
+  todos: TodoGroup[]; // Accept grouped todos as prop
+}
 
-export default function TodoList() {
+export default function TodoList({ studyId, isLeader, todos }: TodoListProps) { // Destructure todos from props
   const navigate = useNavigate();
-  const isLeader = true;
+
+  // If no todos, display a message
+  if (todos.length === 0) {
+    return (
+      <section className="bg-white rounded-[20px] border-[1.5px] border-main3 pt-5 px-5 pb-2">
+        <div className="flex items-center justify-between">
+          <h1 className="text-[18px] font-bold mb-2 text-black1">To-Do</h1>
+          {isLeader && (<button onClick={() => navigate("/CreateToDo", { state: { studyId } })} className="px-2 py-1 bg-main4 rounded-[12px] items-center flex gap-1">
+            <Plus className="text-point" />
+            <span className="text-point text-[14px] font-medium translate-y-[1px] ">새로운 To-Do</span>
+          </button>)}
+        </div>
+        <p className="text-gray-500 text-center py-4">아직 To-Do가 없습니다.</p>
+      </section>
+    );
+  }
 
   return (
     <section className="bg-white rounded-[20px] border-[1.5px] border-main3 pt-5 px-5 pb-2">
       <div className="flex items-center justify-between">
         <h1 className="text-[18px] font-bold mb-2 text-black1">To-Do</h1>
-        {isLeader && (<button onClick={() => navigate("/CreateToDo")} className="px-2 py-1 bg-main4 rounded-[12px] items-center flex gap-1">
+        {isLeader && (<button onClick={() => navigate("/CreateToDo", { state: { studyId } })} className="px-2 py-1 bg-main4 rounded-[12px] items-center flex gap-1">
           <Plus className="text-point" />
           <span className="text-point text-[14px] font-medium translate-y-[1px] ">새로운 To-Do</span>
         </button>)}
       </div>
 
-      {todoGroups.map((group) => (
+      {todos.map((group) => ( // Use todos prop instead of todoGroups mock data
         <div key={group.id} className="space-y-1 pb-2">
           <span className="inline-block px-2 py-1 bg-main4 font-black1 text-[12px] font-medium rounded-[20px]">
             {group.groupName}
@@ -26,10 +48,10 @@ export default function TodoList() {
           {group.todos.map((todo, index) => (
             <TodoItem
               key={todo.id}
-              taskName={todo.taskName}
-              completedCount={todo.completedCount}
-              totalCount={todo.totalCount}
-              isChecked={todo.isChecked}
+              taskName={todo.name} // Use todo.name from API
+              completedCount={todo.completedParticipants} // Use todo.completedParticipants
+              totalCount={todo.totalParticipants} // Use todo.totalParticipants
+              isChecked={todo.isCompleted} // Use todo.isCompleted
               isLast={index === group.todos.length - 1}
               path={`/todo/${todo.id}`}
             />
diff --git a/src/components/UpcomingSchedule.tsx b/src/components/UpcomingSchedule.tsx
index 6c0181a..028da2f 100644
--- a/src/components/UpcomingSchedule.tsx
+++ b/src/components/UpcomingSchedule.tsx
@@ -1,24 +1,51 @@
-import { dummySchedules } from "../mock/scheduleTodoData";
 import UpcomingScheduleItem from "./UpcomingScheduleItem";
+// import { dummySchedules } from "../mock/scheduleTodoData"; // Remove mock data import
 import { useNavigate } from "react-router-dom";
 import Plus from "../assets/plus.svg?react";
+import type { ScheduleItem } from "../types/schedule"; // Import ScheduleItem type
 
-export default function UpcomingSchedule() {
+interface UpcomingScheduleProps {
+  isLeader: boolean;
+  studyId?: string;
+  schedules: ScheduleItem[]; // Accept schedules as prop
+}
+
+export default function UpcomingSchedule({ isLeader, studyId, schedules }: UpcomingScheduleProps) { // Destructure schedules from props
   const navigate = useNavigate();
-  const isLeader = true;
+
+  // If no schedules, display a message
+  if (schedules.length === 0) {
+    return (
+      <section className="bg-white rounded-[20px] border-[1.5px] border-main3 pt-5 px-5 pb-2">
+        <div className="flex items-center justify-between">
+          <h1 className="text-[18px] font-bold mb-2 text-black1">다가오는 일정</h1>
+          {isLeader && (<button onClick={() => navigate("/CreateSchedule", { state: { studyId } })} className="px-2 py-1 bg-main4 rounded-[12px] items-center flex gap-1">
+            <Plus className="text-point" />
+            <span className="text-point text-[14px] font-medium ">새로운 일정</span>
+          </button>)}
+        </div>
+        <p className="text-gray-500 text-center py-4">아직 일정이 없습니다.</p>
+      </section>
+    );
+  }
+
   return (
     <section className="bg-white rounded-[20px] border-[1.5px] border-main3 pt-5 px-5 pb-2">
       <div className="flex items-center justify-between">
         <h1 className="text-[18px] font-bold mb-2 text-black1">다가오는 일정</h1>
-        {isLeader && (<button onClick={() => navigate("/CreateSchedule")} className="px-2 py-1 bg-main4 rounded-[12px] items-center flex gap-1">
+        {isLeader && (<button onClick={() => navigate("/CreateSchedule", { state: { studyId } })} className="px-2 py-1 bg-main4 rounded-[12px] items-center flex gap-1">
           <Plus className="text-point" />
           <span className="text-point text-[14px] font-medium ">새로운 일정</span>
         </button>)}
       </div>
 
-      {dummySchedules.map((item, index) => (
-        <UpcomingScheduleItem key={item.id} item={item}
-          isLast={index === dummySchedules.length - 1}
+      {schedules.map((item, index) => ( // Use schedules prop instead of dummySchedules mock data
+        <UpcomingScheduleItem key={item.id} item={{
+            ...item,
+            scheduleName: item.title, // Map title to scheduleName
+            dateTime: item.scheduleTime || "", // Map scheduleTime to dateTime, handle undefined
+        }}
+          isLast={index === schedules.length - 1}
         />
       ))}
     </section>
diff --git a/src/pages/CreateSchedulePage.tsx b/src/pages/CreateSchedulePage.tsx
index 17e2431..8319b4b 100644
--- a/src/pages/CreateSchedulePage.tsx
+++ b/src/pages/CreateSchedulePage.tsx
@@ -1,53 +1,116 @@
-import { useState } from "react";
-import { useNavigate } from "react-router-dom";
+import { useState, useEffect } from "react";
+import { useLocation, useNavigate } from "react-router-dom";
+import { createSchedule } from "../services/schedule.service";
+import type { CreateScheduleRequest } from "../types/schedule";
 import Header from "../components/Header";
 import LabeledInput from "../components/CreateScheduleToDo/LabeledInput";
-import DateRangeSelector from "../components/CreateScheduleToDo/DateRangeSelector";
-import TimeRangeSelector from "../components/CreateScheduleToDo/TimeRangeSelector";
-import DeadlineSelector from "../components/CreateScheduleToDo/DeadlineSelector";
+import NumberInputBox from "../components/CreateScheduleToDo/NumberInputBox";
 import ActionButton from "../components/ActionButton"; 
 import SuccessModal from "../components/SuccessModal";
 
 export default function CreateSchedulePage() {
   const navigate = useNavigate();
-  // 상태 관리 (입력창과 연결할 데이터)
+  const location = useLocation();
+  const studyId = location.state?.studyId as string | undefined;
+
   const [scheduleName, setScheduleName] = useState("");
   const [place, setPlace] = useState("");
   const [showModal, setShowModal] = useState(false);
+  const [loading, setLoading] = useState(false);
+  const [error, setError] = useState<string | null>(null);
+
+  const today = new Date();
+  const [month, setMonth] = useState<number | string>(today.getMonth() + 1);
+  const [day, setDay] = useState<number | string>(today.getDate());
+
+  useEffect(() => {
+    if (!studyId) {
+      alert("잘못된 접근입니다. 스터디 그룹 페이지로 돌아갑니다.");
+      navigate("/GroupHome", { replace: true });
+    }
+  }, [studyId, navigate]);
+
+  const isDisabled = scheduleName.trim() === "" || loading;
+
+  const formatStartDate = (): string | null => {
+    if (!month || !day) return null;
+    const year = new Date().getFullYear();
+    const formattedMonth = String(month).padStart(2, '0');
+    const formattedDay = String(day).padStart(2, '0');
+    
+    const date = new Date(`${year}-${formattedMonth}-${formattedDay}`);
+    if (isNaN(date.getTime())) return null;
 
-  const isDisabled = scheduleName.trim() === "";
+    return `${year}-${formattedMonth}-${formattedDay}`;
+  }
 
- const handleCreateSchedule = () => {
-    if (isDisabled) return;
+ const handleCreateSchedule = async () => {
+    if (isDisabled || !studyId) return;
     
-    // 폼 데이터 서버 전송 로직 (추가 예정)
-    console.log("일정 생성 데이터 제출:", { scheduleName, place });
+    setLoading(true);
+    setError(null);
 
-    // [수정] 모달 표시
-    setShowModal(true);
+    const startDate = formatStartDate();
+    if (!startDate) {
+      setError("유효한 날짜를 입력해주세요.");
+      setLoading(false);
+      return;
+    }
+
+    const requestData: CreateScheduleRequest = {
+      title: scheduleName,
+      startDate: startDate,
+      location: place || undefined,
+    };
+
+    try {
+      await createSchedule(studyId, requestData);
+      setShowModal(true);
+    } catch (err: any) {
+      console.error("Error creating schedule:", err);
+      setError(err.response?.data?.message || "일정 생성에 실패했습니다.");
+    } finally {
+      setLoading(false);
+    }
   };
 
   const handleConfirm = () => {
     setShowModal(false); 
-    navigate("/GroupHome"); // [요청] 홈 페이지로 연결
+    navigate("/GroupHome", { state: { studyId } });
   };
 
   return (
     <div className="flex flex-col flex-1 min-h-screen bg-white">
       <Header title="일정 생성하기" backPath="/GroupHome" /> 
-      <form className="flex flex-col">
+      <form className="flex flex-col flex-1">
         <LabeledInput label="이름" placeholder="일정의 이름을 적어주세요" value={scheduleName} onChange={(e) => setScheduleName(e.target.value)} />
-        <LabeledInput label="장소" placeholder="장소를 적어주세요" value={place} onChange={(e) => setPlace(e.target.value)} />
-        <DateRangeSelector />
-        <TimeRangeSelector />
-        <DeadlineSelector />
+        <LabeledInput label="장소 (선택)" placeholder="장소를 적어주세요" value={place} onChange={(e) => setPlace(e.target.value)} />
+        
+        {/* Simplified Date Picker */}
+        <div className="flex flex-col gap-3 px-4 pt-5">
+            <label className="text-[16px] font-semibold text-black1">
+                날짜 선택
+            </label>
+            <div className="flex items-center pb-4 border-b-[1.5px] border-main4 gap-2 text-[14px] font-medium text-black1">
+                <NumberInputBox value={month} onChange={(e) => setMonth(e.target.value)} />
+                <span>월</span>
+                <NumberInputBox value={day} onChange={(e) => setDay(e.target.value)} />
+                <span>일</span>
+            </div>
+        </div>
       </form>
-      <ActionButton
-            text="일정 생성하기"
-            onClick={handleCreateSchedule}
-            isDisabled={isDisabled}
-            type="button" 
-        />
+      
+      {error && <p className="text-red-500 text-center mt-4">{error}</p>}
+
+      <div className="mt-auto">
+        <ActionButton
+              text={loading ? "생성 중..." : "일정 생성하기"}
+              onClick={handleCreateSchedule}
+              isDisabled={isDisabled}
+              type="button" 
+          />
+      </div>
+
       <SuccessModal 
         open={showModal}
         onClose={() => setShowModal(false)}
@@ -57,6 +120,5 @@ export default function CreateSchedulePage() {
         message2="생성되었습니다."
       />
     </div>
-
   );
 }
\ No newline at end of file
diff --git a/src/pages/CreateToDoPage.tsx b/src/pages/CreateToDoPage.tsx
index d4e4a9b..47c711f 100644
--- a/src/pages/CreateToDoPage.tsx
+++ b/src/pages/CreateToDoPage.tsx
@@ -1,5 +1,5 @@
 import { useState, useEffect  } from "react";
-import { useNavigate } from "react-router-dom";
+import { useLocation, useNavigate } from "react-router-dom"; // Import useLocation
 import Header from "../components/Header";
 import LabeledInput from "../components/CreateScheduleToDo/LabeledInput";
 import DeadlineSelector from "../components/CreateScheduleToDo/DeadlineSelector";
@@ -10,12 +10,26 @@ import SuccessModal from "../components/SuccessModal";
 
 import type { SelectableMember } from "../types/member";
 import { dummyMembers } from "../mock/memberData";
+import { createTodo } from "../services/todo.service"; // Import createTodo
+import type { CreateTodoRequest } from "../types/todo"; // Import types
 
 export default function CreateToDoPage() {
   const navigate = useNavigate();
-  // 상태 관리 
+  const location = useLocation(); // Initialize useLocation
+  const studyId = location.state?.studyId as string | undefined; // Get studyId from state
+
+  // State management
   const [scheduleName, setScheduleName] = useState("");
   const [showModal, setShowModal] = useState(false);
+  const [loading, setLoading] = useState(false); // For API call loading state
+  const [error, setError] = useState<string | null>(null); // For API call error state
+
+  // State for DeadlineSelector
+  const today = new Date();
+  const [month, setMonth] = useState<number | string>(today.getMonth() + 1);
+  const [day, setDay] = useState<number | string>(today.getDate());
+  const [hour, setHour] = useState<number | string>(today.getHours());
+  const [minute, setMinute] = useState<number | string>(today.getMinutes());
 
   const [selectedMethods, setSelectedMethods] = useState({
     file: false,
@@ -24,11 +38,17 @@ export default function CreateToDoPage() {
 
   const [members, setMembers] = useState<SelectableMember[]>([]);
 
-  useEffect(() => { // 더미 멤버 상태 초기화
+  useEffect(() => {
+    // If no studyId, redirect to group home
+    if (!studyId) {
+      navigate("/GroupHome", { replace: true });
+      return;
+    }
+    // 더미 멤버 상태 초기화
     setMembers(dummyMembers.map((m) => ({ ...m, checked: false })));
-  }, []);
+  }, [studyId, navigate]);
 
-   const toggleMember = (id: number) => {
+  const toggleMember = (id: number) => {
     setMembers((prev) =>
       prev.map((m) =>
         m.id === id ? { ...m, checked: !m.checked } : m
@@ -36,19 +56,83 @@ export default function CreateToDoPage() {
     );
   };
 
-  const isDisabled = scheduleName.trim() === "";
+  // Helper function to format date
+  const formatDateTime = (): string | null => {
+    if (!month || !day || !hour || !minute) return null;
+
+    const currentYear = new Date().getFullYear();
+    // Pad single digits with leading zero
+    const formattedMonth = String(month).padStart(2, '0');
+    const formattedDay = String(day).padStart(2, '0');
+    const formattedHour = String(hour).padStart(2, '0');
+    const formattedMinute = String(minute).padStart(2, '0');
+
+    // Basic validation for date parts (can be more robust)
+    if (
+      isNaN(currentYear) || isNaN(parseInt(formattedMonth)) || isNaN(parseInt(formattedDay)) ||
+      isNaN(parseInt(formattedHour)) || isNaN(parseInt(formattedMinute))
+    ) {
+      return null;
+    }
+
+    try {
+      const date = new Date(`${currentYear}-${formattedMonth}-${formattedDay}T${formattedHour}:${formattedMinute}:00`);
+      if (isNaN(date.getTime())) {
+        return null; // Invalid date
+      }
+      return date.toISOString().slice(0, 19); // Format to YYYY-MM-DDTHH:mm
+    } catch (e) {
+      console.error("Date formatting error:", e);
+      return null;
+    }
+  };
+
+  const isDisabled = scheduleName.trim() === "" || loading;
 
-  const handleCreateSchedule = () => {
-    if (isDisabled) return;
-    const selectedMembers = members.filter((m) => m.checked);
-    console.log("선택된 인증 방식:", selectedMethods);
-    console.log("선택된 멤버:", selectedMembers);
-    setShowModal(true);
+  const handleCreateSchedule = async () => {
+    if (isDisabled || !studyId) return;
+
+    setLoading(true);
+    setError(null);
+
+    const selectedParticipantIds = members.filter((m) => m.checked).map((m) => m.id);
+    const certificationTypes: ("TEXT_NOTE" | "FILE_UPLOAD")[] = [];
+    if (selectedMethods.text) {
+      certificationTypes.push("TEXT_NOTE");
+    }
+    if (selectedMethods.file) {
+      certificationTypes.push("FILE_UPLOAD");
+    }
+
+    const dueDate = formatDateTime();
+
+    if (!dueDate) {
+      setError("유효한 마감 기한을 입력해주세요.");
+      setLoading(false);
+      return;
+    }
+
+    const requestData: CreateTodoRequest = {
+      name: scheduleName,
+      dueDate: dueDate + ":00", // Append seconds to match YYYY-MM-DDTHH:mm:ss format
+      certificationTypes: certificationTypes,
+      participantIds: selectedParticipantIds,
+    };
+
+    try {
+      await createTodo(studyId, requestData);
+      setShowModal(true);
+    } catch (err: any) {
+      console.error("Error creating todo:", err);
+      setError(err.response?.data?.message || "To-Do 생성에 실패했습니다.");
+    } finally {
+      setLoading(false);
+    }
   };
 
   const handleConfirm = () => {
     setShowModal(false);
-    navigate("/GroupHome"); // [요청] 홈 페이지로 연결
+    navigate(`/GroupHome`, { state: { studyId } }); // Pass studyId back to GroupHome
   };
 
   return (
@@ -56,12 +140,18 @@ export default function CreateToDoPage() {
       <Header title="To-Do 생성하기" backPath="/GroupHome" />
       <form className="flex flex-col">
         <LabeledInput label="이름" placeholder="To-Do의 이름을 적어주세요" value={scheduleName} onChange={(e) => setScheduleName(e.target.value)} />
-        <DeadlineSelector />
+        <DeadlineSelector
+          month={month} setMonth={setMonth}
+          day={day} setDay={setDay}
+          hour={hour} setHour={setHour}
+          minute={minute} setMinute={setMinute}
+        />
         <Method selectedMethods={selectedMethods} setSelectedMethods={setSelectedMethods} />
         <SelectMember members={members} onToggle={toggleMember}/>
       </form>
+      {error && <p className="text-red-500 text-center mt-2 px-4">{error}</p>}
       <ActionButton
-          text="To-Do 생성하기"
+          text={loading ? "생성 중..." : "To-Do 생성하기"}
           onClick={handleCreateSchedule}
           isDisabled={isDisabled}
           type="button"
diff --git a/src/pages/GroupHomePage.tsx b/src/pages/GroupHomePage.tsx
index 4c58397..2dffd82 100644
--- a/src/pages/GroupHomePage.tsx
+++ b/src/pages/GroupHomePage.tsx
@@ -9,6 +9,11 @@ import Scheduling from "../components/Scheduling";
 import type { Member } from "../types/member";
 import { getStudyDetail } from "../services/study.service";
 import type { StudyMember } from "../types/group";
+import { getTodosByStudy } from "../services/todo.service";
+import type { GetTodosResponse, TodoGroup } from "../types/todo";
+import { getSchedulesByStudy } from "../services/schedule.service"; // Import the new service
+import type { ScheduleItem, GetSchedulesResponse } from "../types/schedule"; // Import the new type and ScheduleItem
+
 
 export default function GroupHomePage() {
   const location = useLocation();
@@ -22,10 +27,22 @@ export default function GroupHomePage() {
   const [error, setError] = useState("");
   const hasCurrentScheduling = true;
 
+  const [todos, setTodos] = useState<GetTodosResponse>([]);
+  const [groupedTodos, setGroupedTodos] = useState<TodoGroup[]>([]);
+  const [todosLoading, setTodosLoading] = useState(true);
+  const [todosError, setTodosError] = useState<string | null>(null);
+
+  const [schedules, setSchedules] = useState<GetSchedulesResponse>([]); // State for schedules
+  const [schedulesLoading, setSchedulesLoading] = useState(true); // Loading state for schedules
+  const [schedulesError, setSchedulesError] = useState<string | null>(null); // Error state for schedules
+
+
+  const isLeader = members.some(member => member.isLeader);
+
   useEffect(() => {
     // studyId가 없으면 그룹 페이지로 리다이렉트
     if (!studyId) {
-      navigate("/Group");
+      navigate("/Group", { replace: true });
       return;
     }
 
@@ -72,10 +89,80 @@ export default function GroupHomePage() {
       }
     };
 
+    // To-Do 목록 조회
+    const fetchTodos = async () => {
+      setTodosLoading(true);
+      setTodosError(null);
+      try {
+        const fetchedTodos = await getTodosByStudy(studyId);
+        setTodos(fetchedTodos); // Store raw todos
+
+        // Group fetchedTodos by groupName
+        const grouped: { [key: string]: TodoGroup } = {};
+        fetchedTodos.forEach(todoItem => {
+          if (!grouped[todoItem.groupName]) {
+            grouped[todoItem.groupName] = {
+              id: todoItem.groupId, // Assuming groupId is unique for a group
+              groupName: todoItem.groupName,
+              todos: [],
+            };
+          }
+          grouped[todoItem.groupName].todos.push({
+            id: todoItem.id,
+            name: todoItem.name,
+            description: todoItem.description,
+            dueDate: todoItem.dueDate,
+            certificationMethods: todoItem.certificationMethods,
+            isCompleted: todoItem.isCompleted,
+            completedParticipants: todoItem.completedParticipants,
+            totalParticipants: todoItem.totalParticipants,
+            // Map to old Todo properties if still used by TodoItem
+            taskName: todoItem.name,
+            completedCount: todoItem.completedParticipants,
+            totalCount: todoItem.totalParticipants,
+            isChecked: todoItem.isCompleted,
+          });
+        });
+        setGroupedTodos(Object.values(grouped));
+
+      } catch (error) {
+        console.error("To-Do 목록 조회 실패:", error);
+        if (error instanceof AxiosError) {
+          setTodosError(error.response?.data?.message || "To-Do 목록을 불러오는 중 오류가 발생했습니다.");
+        } else {
+          setTodosError("To-Do 목록을 불러오는 중 알 수 없는 오류가 발생했습니다.");
+        }
+      } finally {
+        setTodosLoading(false);
+      }
+    };
+
+    // 일정 목록 조회
+    const fetchSchedules = async () => {
+      setSchedulesLoading(true);
+      setSchedulesError(null);
+      try {
+        const fetchedSchedules = await getSchedulesByStudy(studyId);
+        setSchedules(fetchedSchedules);
+      } catch (error) {
+        console.error("일정 목록 조회 실패:", error);
+        if (error instanceof AxiosError) {
+          setSchedulesError(error.response?.data?.message || "일정 목록을 불러오는 중 오류가 발생했습니다.");
+        } else {
+          setSchedulesError("일정 목록을 불러오는 중 알 수 없는 오류가 발생했습니다.");
+        }
+      } finally {
+        setSchedulesLoading(false);
+      }
+    };
+
+
     fetchStudyDetail();
+    fetchTodos();
+    fetchSchedules(); // Call fetchSchedules
   }, [studyId, navigate]);
 
-  if (isLoading) {
+  if (isLoading || todosLoading || schedulesLoading) { // Update loading condition
     return (
       <div className="bg-background flex flex-col items-center justify-center h-full">
         <p className="text-gray-500">로딩 중...</p>
@@ -98,11 +185,14 @@ export default function GroupHomePage() {
         members={members}
         currentMembers={members.length}
         totalMembers={totalMembers}
+        onViewAllClick={() => navigate("/Member", { state: { studyId, members } })}
       />
       <div className="flex flex-col gap-3 px-4">
         {hasCurrentScheduling && <Scheduling title={"시프 공부하기"} />}
-        <UpcomingSchedule />
-        <TodoList />
+        {schedulesError && <p className="text-red-500 text-center">{schedulesError}</p>}
+        {!schedulesLoading && !schedulesError && <UpcomingSchedule isLeader={isLeader} studyId={studyId} schedules={schedules} />}
+        {todosError && <p className="text-red-500 text-center">{todosError}</p>}
+        {!todosLoading && !todosError && <TodoList isLeader={isLeader} studyId={studyId} todos={groupedTodos} />}
       </div>
     </div>
   );
diff --git a/src/pages/HomePage.tsx b/src/pages/HomePage.tsx
index 4562413..7be0510 100644
--- a/src/pages/HomePage.tsx
+++ b/src/pages/HomePage.tsx
@@ -1,8 +1,124 @@
+import { useState, useEffect } from "react";
 import MyInfo from "../components/MyInfo";
 import TodoList from "../components/TodoList";
 import Calendar from "../components/Calendar/Calendar";
+import { getTodosByStudy } from "../services/todo.service"; // Import todo service
+import type { GetTodosResponse, TodoGroup } from "../types/todo"; // Import todo types
+import { getCalendarSummary } from "../services/calendar.service"; // Import calendar service
+import type { GetCalendarSummaryResponse, ScheduleForCalendar } from "../types/calender"; // Import calendar types
+import { AxiosError } from "axios"; // Import AxiosError for error handling
+
 
 export default function HomePage() {
+  const [todos, setTodos] = useState<GetTodosResponse>([]);
+  const [groupedTodos, setGroupedTodos] = useState<TodoGroup[]>([]);
+  const [todosLoading, setTodosLoading] = useState(true);
+  const [todosError, setTodosError] = useState<string | null>(null);
+
+  const [calendarSchedulesByDate, setCalendarSchedulesByDate] = useState<Record<string, ScheduleForCalendar[]>>({});
+  const [calendarLoading, setCalendarLoading] = useState(true);
+  const [calendarError, setCalendarError] = useState<string | null>(null);
+
+  // For calendar month navigation
+  const today = new Date();
+  const [currentYear, setCurrentYear] = useState(today.getFullYear());
+  const [currentMonth, setCurrentMonth] = useState(today.getMonth()); // Month is 0-indexed
+
+  // Temporary hardcoded studyId for HomePage
+  const tempStudyId = "mock-study-id-for-homepage"; // Use a UUID here in a real app
+
+  useEffect(() => {
+    const fetchTodos = async () => {
+      setTodosLoading(true);
+      setTodosError(null);
+      try {
+        const fetchedTodos = await getTodosByStudy(tempStudyId);
+        setTodos(fetchedTodos);
+
+        // Group fetchedTodos by groupName, similar to GroupHomePage
+        const grouped: { [key: string]: TodoGroup } = {};
+        fetchedTodos.forEach(todoItem => {
+          if (!grouped[todoItem.groupName]) {
+            grouped[todoItem.groupName] = {
+              id: todoItem.groupId,
+              groupName: todoItem.groupName,
+              todos: [],
+            };
+          }
+          grouped[todoItem.groupName].todos.push({
+            id: todoItem.id,
+            name: todoItem.name,
+            description: todoItem.description,
+            dueDate: todoItem.dueDate,
+            certificationMethods: todoItem.certificationMethods,
+            isCompleted: todoItem.isCompleted,
+            completedParticipants: todoItem.completedParticipants,
+            totalParticipants: todoItem.totalParticipants,
+            taskName: todoItem.name,
+            completedCount: todoItem.completedParticipants,
+            totalCount: todoItem.totalParticipants,
+            isChecked: todoItem.isCompleted,
+          });
+        });
+        setGroupedTodos(Object.values(grouped));
+
+      } catch (error) {
+        console.error("HomePage To-Do 목록 조회 실패:", error);
+        if (error instanceof AxiosError) {
+          setTodosError(error.response?.data?.message || "To-Do 목록을 불러오는 중 오류가 발생했습니다.");
+        } else {
+          setTodosError("To-Do 목록을 불러오는 중 알 수 없는 오류가 발생했습니다.");
+        }
+      } finally {
+        setTodosLoading(false);
+      }
+    };
+
+    const fetchCalendarData = async () => {
+      setCalendarLoading(true);
+      setCalendarError(null);
+      try {
+        const calendarSummary = await getCalendarSummary(tempStudyId, currentYear, currentMonth + 1); // API expects 1-indexed month
+        const transformedSchedules: Record<string, ScheduleForCalendar[]> = {};
+        calendarSummary.days.forEach(daySummary => {
+          transformedSchedules[daySummary.date] = daySummary.scheduleTitles.map((title, index) => ({
+            id: `${daySummary.date}-${index}`, // Generate synthetic ID for key prop
+            title: title
+          }));
+        });
+        setCalendarSchedulesByDate(transformedSchedules);
+      } catch (error) {
+        console.error("HomePage 달력 데이터 조회 실패:", error);
+        if (error instanceof AxiosError) {
+          setCalendarError(error.response?.data?.message || "달력 데이터를 불러오는 중 오류가 발생했습니다.");
+        } else {
+          setCalendarError("달력 데이터를 불러오는 중 알 수 없는 오류가 발생했습니다.");
+        }
+      } finally {
+        setCalendarLoading(false);
+      }
+    };
+
+    fetchTodos();
+    fetchCalendarData();
+  }, [currentYear, currentMonth]); // Depend on currentYear and currentMonth for calendar data
+
+  if (todosLoading || calendarLoading) {
+    return (
+      <div className="bg-background flex flex-col items-center justify-center h-full">
+        <p className="text-gray-500">로딩 중...</p>
+      </div>
+    );
+  }
+
+  if (todosError || calendarError) {
+    return (
+      <div className="bg-background flex flex-col items-center justify-center h-full">
+        <p className="text-red-500 text-center px-4">{todosError || calendarError}</p>
+      </div>
+    );
+  }
+
   return (
     <div className="flex flex-col flex-1 min-h-screen bg-white pb-5">
 
@@ -10,31 +126,20 @@ export default function HomePage() {
       <div className="flex flex-col">
         <MyInfo />
         <Calendar
-          schedulesByDate={{
-            "2025-09-08": [
-              { id: "1", title: "시프 과제" },
-              { id: "2", title: "개강" },
-              { id: "3", title: "다죽자" },
-            ],
-            "2025-09-15": [{ id: "4", title: "조별과제 회의" }],
-            "2025-09-22": [{ id: "5", title: "진탐" }],
-            "2025-09-29": [
-              { id: "6", title: "개강" },
-              { id: "7", title: "개강" },
-              { id: "8", title: "개강" },
-            ],
-            "2025-09-30": [
-              { id: "9", title: "과제 제출" },
-              { id: "10", title: "프로젝트 리뷰" },
-            ],
-          }}
+          schedulesByDate={calendarSchedulesByDate}
           onSelect={(date) => console.log("선택된 날짜:", date)}
+          currentYear={currentYear}
+          currentMonth={currentMonth} // Pass 0-indexed month
+          setCurrentMonth={setCurrentMonth}
+          setCurrentYear={setCurrentYear}
+          studyId={tempStudyId} // Pass tempStudyId to Calendar
         />
       </div>
 
       {/* 🔥 UpcomingSchedule + TodoList (위쪽 12px, 좌우 16px 패딩) */}
       <div className="px-4 mt-4">
-        <TodoList />
+        {/* Pass fetched groupedTodos to TodoList */}
+        <TodoList isLeader={false} studyId={tempStudyId} todos={groupedTodos} />
       </div>
 
     </div>
diff --git a/src/pages/MemberPage.tsx b/src/pages/MemberPage.tsx
index db9156c..fa30448 100644
--- a/src/pages/MemberPage.tsx
+++ b/src/pages/MemberPage.tsx
@@ -1,15 +1,35 @@
+import { useLocation } from "react-router-dom"; // useLocation 임포트
 import Header from "../components/Header";
 import MemberInfo from "../components/MemberInfo";
 
-import { dummyMembers } from "../mock/memberData";
+// import { dummyMembers } from "../mock/memberData"; // 더미 데이터 더 이상 필요 없음
 import type { Member } from "../types/member";
 
 export default function MemberPage() {
+    const location = useLocation();
+    const members: Member[] | undefined = location.state?.members;
+
+    if (!members || members.length === 0) {
+        return (
+            <div className="flex flex-col h-full bg-background items-center justify-center">
+                <p className="text-gray-500">멤버 정보를 불러올 수 없습니다.</p>
+                <Header title="스터디 멤버" backPath="/GroupHome" /> {/* 헤더는 계속 표시 */}
+            </div>
+        );
+    }
+
+    // 스터디장을 맨 위로 오도록 정렬
+    const sortedMembers = [...members].sort((a, b) => {
+        if (a.isLeader && !b.isLeader) return -1; // a가 리더, b가 리더 아님 -> a가 먼저
+        if (!a.isLeader && b.isLeader) return 1;  // a가 리더 아님, b가 리더 -> b가 먼저
+        return 0; // 둘 다 리더이거나 둘 다 리더 아님 -> 순서 유지
+    });
+
     return (
         <div className="flex flex-col h-full bg-background">
             <Header title="스터디 멤버" backPath="/GroupHome" />
             <div className="flex-1 overflow-y-auto">
-                {dummyMembers.map((member: Member) => (
+                {sortedMembers.map((member: Member) => (
                     <MemberInfo key={member.id} member={member} />))
                 }
             </div>
diff --git a/src/services/calendar.service.ts b/src/services/calendar.service.ts
new file mode 100644
index 0000000..454e767
--- /dev/null
+++ b/src/services/calendar.service.ts
@@ -0,0 +1,17 @@
+// src/services/calendar.service.ts
+import api from "./api";
+import type { GetCalendarSummaryResponse, GetDailySchedulesResponse } from "../types/calender";
+
+export async function getCalendarSummary(studyId: string, year: number, month: number): Promise<GetCalendarSummaryResponse> {
+  const response = await api.get<GetCalendarSummaryResponse>(`/calendar`, { // Changed from /api/calendar
+    params: { studyId, year, month },
+  });
+  return response.data;
+}
+
+export async function getDailySchedules(studyId: string, date: string): Promise<GetDailySchedulesResponse> {
+  const response = await api.get<GetDailySchedulesResponse>(`/calendar/${date}`, { // Changed from /api/calendar/${date}
+    params: { studyId },
+  });
+  return response.data;
+}
diff --git a/src/services/schedule.service.ts b/src/services/schedule.service.ts
new file mode 100644
index 0000000..2bb1d05
--- /dev/null
+++ b/src/services/schedule.service.ts
@@ -0,0 +1,19 @@
+// src/services/schedule.service.ts
+import api from "./api";
+import type { CreateScheduleRequest, CreateScheduleResponse, GetSchedulesResponse } from "../types/schedule";
+
+export async function createSchedule(
+  studyId: string,
+  data: CreateScheduleRequest
+): Promise<CreateScheduleResponse> {
+  const response = await api.post<CreateScheduleResponse>(
+    `/studies/${studyId}/schedules`,
+    data
+  );
+  return response.data;
+}
+
+export async function getSchedulesByStudy(studyId: string): Promise<GetSchedulesResponse> {
+  const response = await api.get<GetSchedulesResponse>(`/studies/${studyId}/schedules`);
+  return response.data;
+}
\ No newline at end of file
diff --git a/src/services/todo.service.ts b/src/services/todo.service.ts
new file mode 100644
index 0000000..0fd2076
--- /dev/null
+++ b/src/services/todo.service.ts
@@ -0,0 +1,19 @@
+// src/services/todo.service.ts
+import api from "./api";
+import type { CreateTodoRequest, CreateTodoResponse, GetTodosResponse } from "../types/todo";
+
+export async function createTodo(
+  studyId: string,
+  data: CreateTodoRequest
+): Promise<CreateTodoResponse> {
+  const response = await api.post<CreateTodoResponse>(
+    `/studies/${studyId}/todos`,
+    data
+  );
+  return response.data;
+}
+
+export async function getTodosByStudy(studyId: string): Promise<GetTodosResponse> {
+  const response = await api.get<GetTodosResponse>(`/studies/${studyId}/todos`);
+  return response.data;
+}
\ No newline at end of file
diff --git a/src/types/calender.ts b/src/types/calender.ts
index a1fee0a..9a0f1ff 100644
--- a/src/types/calender.ts
+++ b/src/types/calender.ts
@@ -5,6 +5,30 @@ export type ScheduleForCalendar = {
   title: string;
 };
 
+export interface CalendarDaySummary {
+  date: string; // "YYYY-MM-DD"
+  scheduleTitles: string[];
+}
+
+export interface GetCalendarSummaryResponse {
+  year: number;
+  month: number;
+  days: CalendarDaySummary[];
+}
+
+export interface DailySchedule {
+    title: string;
+    location?: string;
+    scheduleTime: string; // e.g., "2024 1 15 14:00"
+    dDay: number;
+}
+
+export interface GetDailySchedulesResponse {
+    date: string; // "YYYY-MM-DD"
+    schedules: DailySchedule[];
+}
+
+
 // "2025년 9월 19일 (금) 오후 00:00" → Date 객체로 변환
 function parseKoreanDate(str: string): Date {
   return new Date(
diff --git a/src/types/schedule.ts b/src/types/schedule.ts
index e877462..a0070bb 100644
--- a/src/types/schedule.ts
+++ b/src/types/schedule.ts
@@ -1,11 +1,13 @@
 export interface ScheduleItem {
-  id: number;
-  location: string;
-  scheduleName: string;
-  dateTime: string;
-  dDay: number;
+  id: string; // API 응답에 맞춰 string (UUID)
+  title: string; // 일정 이름
+  location?: string; // 장소 (선택사항)
+  scheduleTime?: string; // YYYY M DD HH:mm 형식 (확정된 일정만)
+  dday?: number; // 오늘 기준 남은 일수 (확정된 일정만)
 }
 
+export type GetSchedulesResponse = ScheduleItem[]; // GetSchedulesResponse는 ScheduleItem의 배열
+
 export interface TimeSlot {
   hour: number;
   minute: number;
@@ -39,3 +41,15 @@ export interface ScheduleData {
   maxMembers: number; // 최대 인원
   cells: ScheduleCell[]; // 모든 셀 데이터
 }
+
+export interface CreateScheduleRequest {
+  title: string;
+  startDate: string; // "YYYY-MM-DD"
+  location?: string;
+}
+
+export interface CreateScheduleResponse {
+  id: number; // The ID of the newly created schedule
+}
+
+
diff --git a/src/types/todo.ts b/src/types/todo.ts
index 95dd3ac..25f6a32 100644
--- a/src/types/todo.ts
+++ b/src/types/todo.ts
@@ -8,25 +8,21 @@ export interface TodoMember {
   isMe?: boolean; // 현재 사용자인지 여부
 }
 
-export interface TodoData {
-  id: number;
-  groupName: string;
-  title: string;
-  completedCount: number;
-  totalCount: number;
-  dueDate: string;
-  progress: number;
-  completedMembers: TodoMember[];
-  incompleteMembers: TodoMember[];
-  isUserCompleted?: boolean; // 현재 사용자가 완료했는지 여부
-}
-
+// 기존 Todo 인터페이스를 API 응답에 맞춰 업데이트
 export interface Todo {
   id: number;
-  taskName: string;
-  completedCount: number;
-  totalCount: number;
-  isChecked: boolean;
+  name: string; // API 응답의 '이름' 필드
+  description?: string; // API 응답의 '설명' 필드
+  dueDate: string; // API 응답의 '마감일' 필드
+  certificationMethods: ("TEXT_NOTE" | "FILE_UPLOAD")[]; // API 응답의 '인증 방식' 필드
+  isCompleted: boolean; // API 응답의 '완료 상태' 필드 (현재 사용자 기준 또는 전체)
+  completedParticipants: number; // API 응답의 '완료된 참여자 수' 필드
+  totalParticipants: number; // API 응답의 '전체 참여자 수' 필드
+  // 기존 ToDoItem에서 사용되던 필드 중 필요한 것들을 유지
+  taskName?: string; // 기존 TodoItem과 호환성을 위해 유지
+  completedCount?: number; // 기존 TodoItem과 호환성을 위해 유지
+  totalCount?: number; // 기존 TodoItem과 호환성을 위해 유지
+  isChecked?: boolean; // 기존 TodoItem과 호환성을 위해 유지
 }
 
 export interface TodoGroup {
@@ -34,3 +30,31 @@ export interface TodoGroup {
   groupName: string;
   todos: Todo[];
 }
+
+export interface CreateTodoRequest {
+  name: string;
+  dueDate: string; // ISO 8601 format, e.g., "YYYY-MM-DDTHH:mm:ss"
+  certificationTypes: ("TEXT_NOTE" | "FILE_UPLOAD")[];
+  participantIds: number[];
+}
+
+export interface CreateTodoResponse {
+  id: number; // Assuming the created todo has an ID
+}
+
+// 새로운 API 응답을 위한 인터페이스
+export interface GetTodoItemResponse {
+  id: number;
+  name: string;
+  description?: string;
+  dueDate: string;
+  certificationMethods: ("TEXT_NOTE" | "FILE_UPLOAD")[];
+  isCompleted: boolean; // 완료 상태 (현재 사용자 기준)
+  completedParticipants: number;
+  totalParticipants: number;
+  groupId: number; // 어떤 그룹에 속한 todo인지 식별하기 위해 추가
+  groupName: string; // 그룹 이름을 직접 제공하면 유용
+}
+
+export type GetTodosResponse = GetTodoItemResponse[];
+