How to allow play multiply games from one steam account? [closed]

My bro buy Pubg, and he gives this game for my account and now When I play CS:GO him is cant play Pubg :( Problem: One login = One Game. How to One login = Two other games?

As said in the QA of Steam Sharing you can't:

Can two users share a library and both play at the same time? No, a shared library may only be accessed by one user at a time.

When I authorize a device to lend my library to others, do I limit my own ability to access and play my games? As the account holder, you may always access and play your games at any time. If you decide to start playing when another user is already playing one of your games, he/she will be given a few minutes to either purchase the game or quit playing.