I follow this tutorial: https://guides.github.com/activities/hello-world/

I live in zurich and want to learn all this GitHub because it looks very useful.

I do code in Unity engine and am wondering if code for games could also be stored and edited here.

how can I delet "old" branches? - done

Next: read this: https://guides.github.com/introduction/flow/ and check this place too: https://github.com/explore

The other guides can be found here: https://guides.github.com and follow this channel on youtube: https://www.youtube.com/githubguides or watch it here: https://www.youtube.com/channel/UCP7RrmoueENv9TZts3HXXtw