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It was some packard bell PC with windows xp, and a 1.9 GHz pentium 4

This is for running Linux programs on Windows. ELI5: some programs are made to run on windows, and some programs are made to run on Linux. Microsoft made a thing for windows that makes it able to run programs that were supposed to run on Linux. That thing is called Windows Subsystem for Linux.

What windows programs do you have that are not working well on Linux? There are various tools to run windows programs on Linux, and some work better than others for specific programs. I have had good luck with bottles recently, you might try that if you have not already. Other options I've used with great success in the past: ploy on Linux, Lutris, and wine directly. They all us wine at some level, but have tried and tested configuration for various programs to run well, and help with the installation and management of different wine versions. Depending on your windows programs, one option might be to run windows in a VM on Linux, to run those few programs. Another benefit of this way is that your Linux system is somewhat isolated from your windows programs. This can help with privacy and security.

I see what you mean. Yes there are great examples like those that offer support contracts for the open source software projects.

I think one point of confusion here is that as open source licenced projects, they do not restrict commercial use. The companies that lead the development just happen to also offer the best paid support.

Minor correction: proxmox is AGPL so free to use commercially without their support contract.

Ubuntu and LibreOffice are both free for commercial use. Or am I misunderstanding what you mean?

It's no longer open source if you restrict commercial usage. Sure, licence your software that way if you want to, but don't call it open source.