How to push only your own files to git?

Question

git

Good afternoon, Zak added to a private repo, there are two branches, one master is the second developer, Zak asks me to make commits to the master branch, the master branch contains only the backend, I did a git clone and locally created the frontend directory, can you tell me how -to commit only what relates to the frontend, those changes that relate to my work, I don’t quite understand if I’m going to commit my work, I’ll re-upload the entire old backend with my frontend, or do I need to download everything before my commit every time, in In general, I do not understand how it should be, tell me.

Answer 1

https://git-scm.com/book/ru/v2 urgently study, move the mess out of your head to a more appropriate place.
after that, more specific questions can be asked here.