This is a zillion-times duplicate question but,
1) git is for source control. "source" means small text files (ASCII files), being computer languages.
You don't use git, at all, for things like filmmaking, game production, in a music studio, the TV business, etc.
The game industry generally runs on subversion.
(Unity projects have four or five tiny "source" files, and then gigabytes of video, animation, textures, models etc. It's just totally unsuitable for git.)
2) If for some reason you are trying to use git with a Unity project. FYI the usual suggestion,
simply use the actual up-to-the-minute official plan FROM GIT THEMSELVES:
https://github.com/github/gitignore/blob/master/Unity.gitignore
Hooray!
You often see long-winded discussions about "how to use git with Unity", this is bizarre as (the best you can do with git) is right there, courtesy git git.
Just to repeat, do note that it is incredibly easier to use svn with Unity. svn is made for media, film, game etc projects. Git is really for source (i.e. computer code files). Unity projects have a few hundred bytes computer code ASCII files, and very often 100s of gigabytes of music, video, texture, modelling etc assets. You're knocking yourself out using git for no reason.
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