Where to get a legitimate Windows 11 pro key?

 

I'm trying to be frugal with my new PC build. I don't see the point in wasting a few hundred dollars on the operating system when that could be better spent on my actual specs to increase the performance of my PC. https://www.reddit.com/r/GetComputerHelp/comments/1d8nwb8/where_to_get_a_legitimate_windows_11_pro_key/