As others have said, you don’t need to know how to code, but you do need to be comfortable editing structured documents, so knowing a little programming does help.
Unfortunately, Nextcloud and email are two of the most difficult things to self-host. This is by reputation, I haven’t tried myself. Email is supposed to be particularly difficult and the usual advice is to not bother.
Jellyfin is pretty straight-forward as long as you don’t have a weird hardware decoding setup and as long as you don’t want remote access. If you do want remote access you need to use third party tools to do it securely. If it’s just for your own use then Tailscale makes it really easy. If you want to share with non-technical users it gets messy.

Home Assistant can track Jellyfin playback status, so there’s some kind of API there. Whether or not there’s a convenient way to trigger the tasks is another question.

Sears & Roebuck

AWS

I’ve got Pentiment and Persona 5 ready to go. I’ll probably start Pentiment first since it’s undoubtedly shorter.
Balatro looks really tempting, too, but I’d want that for my laptop or phone (?) and not my gaming PC.

I use Portainer mainly to start / stop / restart containers without the mental load of using the command line. It works fine with Compose if you can get (or write) a yaml file for the container you’re interested in, or you can use it to pull from the repository and set everything up if you can’t. Portainer also gives you a nice, one-stop view of the current state of your containers. Basically, it can’t hurt to have it around.
Personally, my favorite Docker management GUI is the one that comes with Synology NASes. It’s much less clunky that Portainer and iirc a little more powerful. But of course it only runs in their hardware.