The most efficient way to activate Windows without manually downloading files is using a direct PowerShell/CMD command that pulls the script directly from a trusted GitHub source. Method 1: The "One-Line" PowerShell Command
If you have an old Windows 7, 8, or 8.1 key, try activating Windows 10 with it. Microsoft allowed free upgrades until 2016, but many keys still work today via CMD: activate windows 10 cmd github