Can someone explain a easy way to make a repository for my game as I have never made one and would love to participate in this game jam. I use Unity 2021.3.5 and Visuial Studio 2022. I have tried to look up tutorials of how to use github and I understand how it works but i dont know how I should set up a repository for my game.

I think I could explan the basics. have made repo for Unity project on last year GameOff :)
You want explanation here or on discord or something?

Make a new repository on github. Then you can download Github Desktop to clone it on your computer and every time you make changes on your local files, you can push them to your repository through github desktop