I relaunched my #Git tutorial! It gets you from being able to use Git to actually understanding it in less than fifteen minutes.
It is now also usable on smaller screens, looks a bit more modern, and is now up-to-date with modern Git features and conventions.
Git it a try at https://agripongit.vincenttunru.com
I built the original in 2015 with a number of learning goals, among which were actually finishing projects, and React. Over the years several people have taken the effort of actually reaching out to me to share how it's been helpful to them, which has been very gratifying.
Rebuilding it was a good way of reflecting on both how much I've learned since then, and how much our tooling has improved.
Server run by the main developers of the project 
It is not focused on any particular niche interest - everyone is welcome as long as you follow our code of conduct!
For example, there were a number of typo's in the original that I wasn't able to fix, because lockfiles weren't a thing in the JS ecosystem back then, and I could not figure out the right combination of dependencies to properly build it!