Hi indradeo,
Refer below sample.
HTML
CS.aspx
<head runat="server">
    <title>Calendar</title>
</head>
<body>
    <form id="form1" runat="server">
        <asp:Calendar ID="Calendar1" runat="server" ></asp:Calendar>
        <br />
        <asp:Button ID="btnCalendar" runat="server" OnClick="OnDateSelected" Text="Submit" />
    </form>
</body>
Home.aspx
<head runat="server">
    <title>Home</title>
</head>
<body>
    <form id="form1" runat="server">
        <h1>Selected Date:</h1>
        <asp:Label ID="lblSelectedDate" runat="server"></asp:Label>
    </form>
</body>
Code
CS
protected void OnDateSelected(object sender, EventArgs e)
{
    DateTime selectedDate = Calendar1.SelectedDate;
    string date = HttpUtility.UrlEncode(selectedDate.ToString("yyyy-MM-dd"));
    Response.Redirect("Home.aspx?date=" + date);
}
Home
protected void Page_Load(object sender, EventArgs e)
{
    string encodedDate = Request.QueryString["date"];
    string selectedDate = HttpUtility.UrlDecode(encodedDate);
    lblSelectedDate.Text = selectedDate;
}
Screenshot
