One method is to enter 'wmic path SoftwareLicensingService get OA3xOriginalProductKey' in Command Prompt This article ...
If your PC is compatible, it’ll handle the upgrade for you, and beyond updating a few drivers, you shouldn’t have to do much ...
Windows 10 is installed thousands ... the same purposes as the product key. Even better, it's built into the OS - this means that if you need to reinstall or upgrade Windows, you won't need ...