Most "free" activation methods found on GitHub don't actually give you a unique, permanent product key. Instead, they use one of the following:
If you found a GitHub repo claiming to provide working product keys, I’d recommend reporting it to GitHub as a potential policy violation — those keys are often stolen or counterfeit, and using them could put your system at legal and security risk. windows 81 product key github free
files from unverified repositories claiming to be "key generators." Stick to open-source scripts where you can read the code. Most "free" activation methods found on GitHub don't