Yeah, I use systemd for the self-host stuff, but you should be able to use docker-compose files with podman-compose with no, or only minor, changes. Theoretically. If you’re comfortable with compose, you may have more luck. I didn’t have a lot of experience with docker-compose, and so when there’s hiccups I tend to just give up and do it manually, because it works just fine that way, too, and it’s easier (for me).
Honestly, find an existing project in your language of choice with an active maintainer and start fixing tickets.
You start a new project, odds are you’re stuck maintaining it for years, and it becomes a job, or it dies. IME, it’s far better to find a project you yourself use and like, that you’re capable of contributing to, and doing that. Start popping stuff off the bug list, if you’re a hero, or implement that missing feature in the backlog that you want. Your commitment to the project is a patch. Or, maybe you like working with the project and you become a long term contributor.
That’s just my recommendation. I’m not saying don’t start something new; just, if you’re looking around for things to do, and aren’t passionately trying to scratch an itch you haven’t found a solution for, you’re most likely just going to create a throw-away project.
Just my opinion.