Can Windows 11 computers be compatible with old software?

I'm currently using Windows 11 and I have some older software that I rely on for work, but I'm not sure if they'll run properly on this new operating system. Can anyone tell me if Windows 11 is compatible with older programs, what issues I might run into, and whether there are any workarounds like compatibility mode or virtual machines that actually work for getting legacy software to function without crashing or losing features?