Top G refers to a quote by Andrew Tate's father:
It's a very important quote because if you do the following:
Then, you will become a feared opponent in everything you do.
That is why if people try to compete against Andrew Tate, they become intimidated.
It doesn't matter what it is. If you're up against Tate in anything, part of you is going to be like “uh not him, is there anyone else?”
This is what it means to be a Top G.