Jellyfin expects movies to be in sub-folders with their movie titles for the best experience. You can have a Star Trek library, but each movie inside of there needs to be in its own folder. For example M:\Star Trek\Star Trek II - Wrath of Kahn\Star Trek II - Wrath of Kahn.mkv

This has always worked the best for me.

Not my title. Original video owner’s title.

I just linked directly to youtube? I don’t even know how I did it lol. Still new to this.