How to make Universe gui?

Hi, I was wondering how I could make a universe gui. For example, you go to a game and there is a start screen that says "join game" or something like that. And when you click on it, you enter a different game via "Universes"

any idea how to do that?

Just make a gui button and when the players click the button, then make it invisible and the universes "visible" and if they hit the button, teleport them.