I think it is simple until you make a mistake.
I am a very basic user of git, with one or two branches and straight merges.
Until I commit the wrong thing, or mess with the merge and end up with a set of files I did not create (.orig IIRC).
So git is simple but not simply forgiving (it may be forgiving, but you need to know more). https://ohshitgit.com/ helped me several times.