Upgrade from Windows 8.1 Pro to Windows 10.
Upgrade from Windows 8.1 Pro to Windows 10.
You can perform a clean installation. The activation will be permanent unless you choose otherwise. Upgrading is possible, though compatibility issues with older drivers from Windows 8.1 may arise.
It should work without issues, and you'll retain all your files. If you prefer not to use Windows 10, you can revert to Windows 8.1. ;D
Absolutely, back it up if you're hesitant. I'll ensure everything goes smoothly when you do it correctly!