I also use restic for backups. I actually switched from Borg because it kept getting stuck and failing but couldn’t work out why. Not had issues with restic (so far, touch wood!).

I use resticprofile with yaml configurations though (https://github.com/creativeprojects/resticprofile), which made it much easier for me to figure out.

I use borgbase for offsite backups.

They really push you to install the aio container so it’s not surprising to me.

If you’re comfortable in the terminal you’ll be fine just starting out and figuring it as you go. Be ready for a few reinstalls but it becomes part of the fun, albeit sometimes frustrating! Go for a mainstream server os like Ubuntu or Debian (as if you google them with any issue you’re likely to find at answer). Get SSH up and running with keys for security, install tailscale and don’t expose to the internet until you feel more comfortable. Install docker then start on one software you think will be useful, get it up and running then move onto the next. I would recommend homepage as a front end then keep it up to date with new software so you can quickly see what you have and what ports are in use. Vaultwarden is useful for the admin passwords. I use authentik for sso but would try caddy if I was starting now.