How does git keep track of versions in the remote repository?

Question

What I understand is that when make a push, my code in the remote repository gets updated. How does git actually keep track of the versions of the release (in context of git

Answer 1

It updates remote tracking branches (branches in the remotes namespace).

Those have the last SHA1 fetched from the remote in them.

See "Git: What is a tracking branch?"

This isn't limited to "git-flow", it is a basic git mechanism.