How to show a pop-up web-form in asp.net C# ?

Hello, I am developing a web application.
Here is where I am:-
I have a grid view that lists the members in the website. Along with the names, there is a button control too. What I require is that, when I click on the button, a pop-up webform should appear within the context of the current webform. The popup webform should have web form controls like textbox, labels, button to save the new edits, etc. On clicking the button, the "saves" should be made.
How do we create such a form?
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