You can simply run Windows 11 for free. This is possible but you'll have an ugly permanent watermark that will overlay everything and the features you'll be able to use will be limited. There are also ways to pirate Windows with scripts. I would highly advise against these methods as I've had many people come into my IT store with there PC's completely bricked from trying to do this. These scripts are also not audited by anyone for legitimacy and could very well be backdoors for hackers to access your personal information. You're better off just sourcing a Windows 11 key cheap or keeping your Windows inactivated and dealing with the Watermark. You often hear the term "Grey market keys" thrown around. It often carries a negative stigma. People will often claim that these types of keys have been paid for with stolen credit cards and aren't legitimate. This isn't necessarily true. It is entirely possible to acquire Windows keys through a third party that isn't Microsoft that are perfectly legitimate. Often, when an office clears out and decommissions their computers, they are recycled for parts or refurbished for resale. You can resell the operating system so long as it has been deactivated on that computer.