If you want to master Git and GitHub fast, you have to know about these resources:
Git Tutorials by Atlassian
Git Crash Course by Programming with Mosh
Git cheatsheet by Atlassian
https://www.atlassian.com/git/tutorials/atlassian-git-cheatsheet
Git Official Docs
Become a Git & GitHub Expert
Git & GitHub Youtube Course
GitHub Minesweeper
Oh, My Git!
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