2019 MacBook Pro - is Monterey necessary?

An update is available. I’m running Catalina. I don’t have enough disk space. I asked Siri how I could free up disk space. I get 3-4 articles about Windows PC. I ask a more specific Q. about disk space on my MacBook. She says, “Sorry I can’t help you.” WTF?

So, should I bother? And if I go ahead can I easily uninstall those apps I never use, like GarageBand, Chess, Maps?