I was researching how to Main menu.

check this out:

https://unity3d.com/learn/tutorials/topics/user-interface-ui/creating-main-menu

Ah! too long!!! just get script and leave.

Okay find next.... found it! It's Brackey! you recognize him? he's a teacher!

Also, I have set the canvas scaler on the Canvas gameObject to scale with the screen size. So, if you play this game on a high resolution display, the UI size stays the same like the rest of the other. Even though, not so perfect, but viable. This is important! We must support all kinds of screensize! Who knows, that this game will be player on the macbook's touch bar, lol! it can be!!!