You're looking for a guide related to activating Windows 8.1 using a tool from GitHub. I must emphasize that using activators or cracks to bypass Windows activation can be risky and potentially harm your system. It's always recommended to purchase a genuine copy of Windows from Microsoft or an authorized retailer.
When researching this keyword, you will encounter several well-known (or notorious) names: github windows 8.1 activator
Activated versions of Windows may not receive updates from Microsoft, including security updates. This can leave your system vulnerable to security threats. Moreover, you might not be eligible for technical support from Microsoft. You're looking for a guide related to activating Windows 8
Activate Windows 8, 8.1, 10 and 11 Pro for Free - GitHub Gist github windows 8.1 activator