One way to achieve state with a CGI solution is for the first CGI program to write out HTML that includes another form.
Some of the information the CGI program knows, like the user name from the first form, is written out as hidden form fields in the HTML.
The ACTION parameter on this second form is another CGI program, and this second CGI program will have all the information from the first form as well as from the second.
This technique works, but it is difficult to write, and harder still to maintain when your forms change.