Sonarr, and radarr adds movies, and tv show to you library.
You need to configure jackett/prowlarr for Sonarr, and radarr to find torrents(torrentleech/galaxy etc). For a couple of the torrent websites you might need a VPN to access those reliably.
You would also need a torrent client for them to download torrents. Or configure Usenet.
Jellyfin/Plex will find the media downloaded, and you can use the clients of these to watch media wherever you want.
After configuring Sonarr/radarr you can use jellyseerr/overseerr to add media to them easily.
I use them on docker but I think you can use docker/containers in truenas too.