Newb question on where to start backups?

Hello so I've been messing around with proxmox etc. Can someone give me tips on what to learn to backup the proxmox environment?

Is there a way to do this?

I run home assistant / plex / truenas scale VM.

Can I backup these aswell?

If my CPU dies tmrw would I even be able to have access to my truenas vm after this?

Newb sorry but just tips or starting points for researching what I need to learn to be safer.