How to make buttons actualllly work for main menu

ok so Ive made a main menu screen for our next cool game and I need help with making the button switch to the game. And when you click the button it does work.
Heres the link:PlayCanvas | HTML5 Game Engine
To the project:https://playcanvas.com/project/601327/overview/zombaniaio

A post was merged into an existing topic: I cant find out how to make a main menu!