Radarr is Movies only. You'll add your indexer username/password into it for it to search for movies you want. You'll add sabnzbd for it to automatically download the movies. The download folder will need to be the same folder radarr has access to to move it to the complete folder.
The complete folder will be where Plex/jellyfin/whatever library is.
Sonarr is exactly the same thing but it is for TV shows.
I'm out until tomorrow evening. Once I get back home I can look at my setup and provide more specifics.
Basically you add everything into sonarr/radarr and it should do all the work for you. You just tell it what you want.
Yep, that's exactly what it does.
Sonar settings profiles - What version and quality of TV you're looking for.
settings indexers - This is where you'll put your DS account. Plus button, Newznab under "presets" you'll see DS. Add your API key and test.
settings downloadclients - This is the URL/IP to sab, you'll need to set it up and get an API key from it.
settings connect - This is where you can link Plex to tell it there's a new ep.
Lets say you add Superjail to Sonarr in Series -> Add new. It'll watch your indexer (DS) for that. as soon as the ep is on DS it'll download the nzb and send it to sabnzbd. SAB will download it from your usenet provider.
In sab -> config -> folders the "Completed Download Folder" needs to be the exact same and accessible from sonarr. Mine is /downloads/complete/ this folder needs to be the same exact in SAB and Snoarr. The other thing in SAB is you need to put your usenet provider under sab.example.ca/config/server/. The other settings are useful, read them, set labels, etc.
Once SAB is done downloading it, it will be put into /downloads/complete/ and Sonarr will pick it up and move it to the Libary location Sonar has setup for Superjail
Good luck!