Hello all, I'm new to this forum

I didn't really know what to type in the Title of the thread.. I'm sorry if I confused someone, alse I don't know if this is the right place to post this, feel free to move it.

I have a little problem with my gui app. I have a school project of creating a program with registration form and after logging in it gives you a list of applications that can be used. Games and Chat in my case.
All of them are network connected, they have a server and client app (multi thread chat, Tic Tac Toe and Backgammon)

So what I want to do is, on a button click (let's say TicTacToe) to open that app. If you are hosting the server automatically starts reading your IP, and if you Join to give you list of servers. Is there any way that I can do this without using multiple applications, I mean.. to open the game as a new window in the existing app? I suppose for that to work I'll need to edit my code in every app I have.. Am I supposed to use JDialogs or what?
I haven't work with more than one JFrame(JPanel) in Java so this is confusing for me

Thanks for helping
I hope you understood what I want :D