hello ramcab,
you can search your record on button click event after enter the id in textbox. and store the result in session or query string to pass to another form. and set that value in texbox of that form.
loke :
Session["name_of_student"]=abc;
use Response.Redirect() or what ever you wanna use to open new form.
and set value like :
txtbox.Text=Session["name_of_student"].ToString();
Hope this will help you.
Don't forget to mark as answer if it helps. :)