Apple TV Function

• Local affiliates of nationwide networks are often available in the main network’s app, based on IP geolocation.
• If a local TV station publishes an app for Apple TV/tvOS, then that is possible.
• If you have an antenna, an HDHomeRun box, and the Channels app, then you can watch over-the-air broadcasts on Apple TV.

the appletv box is sort of like an ipad that use your tv as display all it's functionality comes from apps you install from app store, it does not interface with an antenna or disc or cable to get tv signals, so if your local tv channels provider does not have an app in app store you can't view your local tv channels.