UI creation guide

Hi,

I am look for a nice UI guide on how to make buttons and switch between scenes for Unity.
I have tried several general unity UI guides (non were for Oculus Go), but my buttons doesn't work and I don't know which render mode to choose.

Does anyone have a nice tutorial?
I basically only want to know how to make a button that switches between scenes and is possible to activate with the Oculus Go controller. 

I hope someone can help me.