So, me and my friend want to work together for this Game Jam, but have never worked as a team before, and have no idea how to work on the same Unity project from two different locations. I know they mentioned something about GitHub, but I have no idea how to use it or how I would set it up. If anyone could help me find out how, either by linking to a tutorial they recommend, or straight up telling me, that would be great.

Also, we have a course for this very purpose! https://www.gamedev.tv/p/git-smart-course/?coupon_code=GAMEJAM_OFFER

The key to not stepping on each other's toes is to not be working on the same files at the same time. Divide up the work and have a seperate scene file each as scene files are impossible to merge.