how to access datetime from database.....

Assuming that you have the values available in the code and that you have created 2 labels on the page like so:

<asp:Label ID="Label1" runat="server"/>
<asp:Label ID="Label2" runat="server"/>

in code (perhaps in an OnLoad method):

string start = db.Date1;
string end = db.Date2;

Label1.Text = start;
Label2.Text = end;

where db.Date1 and db.Date2 represent the values extracted from the database (however you have made that happen).

Note that the above is very simplistic: you'll need to alter to suit your requirement.