I haven’t used an ARM system, but docker might be the best bet? Get docker installed and find instructions for install Jellyfin and each arr program.

https://forum.armbian.com/topic/11654-is-it-possible-to-install-docker-fresh-latest-build/

If you’re in the U.S.:

1. Create a fake credit card with Privacy
2. Set the purchase limit to $0.
3. Create a temporary email
4. Start a 7-day trial on Medici.tv
5. Use a video downloading tool to grab what you want.

Truthfully, I don’t know if step 4 5 will be easy. I’ve used OBS to do screen records of encrypted content. But that takes a long time to do, so maybe there is more information out there about ripping web video?