

Maybe a easier place to start is a beginner friendly system? Lots of people like running Unraid for example, and they have lots of apps that will make it easier to get into (https://ca.unraid.net/), that might help ease them into it. Being thrown into a Linux terminal might feel daunting, but also a great way to learn.
I think many just need to get hooked on it, then they more naturally feel like they want to customize and try out stuff.
I dont have any guide recommendations, since its been a while since I started. You can probably do some searching on the stuff you want them to setup.

For the arr stack the best resource I know is https://wiki.servarr.com/ which I referenced for my setup in Kubernetes.
Most projects have pretty good documentation on how to setup their services, in many cases its just the Docker config afterall.