asp.net webforms c# and jQuery

Question

Using ASP.NET  C# webforms can someone show me how to use jQuery to open a modal that with two button save cancel  this would also contain a text box that must have a value entered before the save button is allowed so I would use the RequiredFieldValidator it value is entered the user would press save and it would call a delegate on the parent page saying something has been successfully posted. A Message would then say success + textbox.Text;

Perhaps my thoughts are wrong I am tying to do postbacks to the server using  server controls in asp.net. What are best practice?
I just want to get  a feel for how to use jQuey with Asp.Net Webforms.

thanks in advance.