In the new macOS Catalina, Apple is “replacing iTunes with its popular entertainment apps — Apple Music, Apple Podcasts and the Apple TV app.”
And yes, it’s just Apple TV for both movies and TV shows; there isn’t an Apple Movies app.
When Apple TV is up and running (and iTunes is laid to rest once and for all) what ever films and TV shows you own will be shifted from the library section of iTunes to the library section of Apple TV.
R.I.P. iTunes. Or maybe that should be RiP iTunes. They never did capitalize that ‘i’ for whatever reason.