Git remove root commit

I can't do a lot of things with git and I want to remove a commit from my repo, because I uploaded wrong stuff.

I used git revert but since the commit is root and I can't remove it. fatal: Cannot revert a root commit

What to do in that case ?

Please don't give me links to other topics here, I read them and I don't understand what to do, I need some basic example about removing some commit.