If you don’t have a Windows product key you are using a non-activated version, with windows 11 pro key you can upgrade to the full version at any time. Of course, you can buy the full Windows 11 from Microsoft, but there are many places where you can get keys cheaper. You can buy cheap Windows keys on Amazon, too, but always look at customer reviews. Negative ones may do a good job of showing where the key came from and showing you whether the key is legit or a gray market…