Restrict access to content in the Apple TV app
You can configure the Apple TV app 
to restrict certain content so that only authorized users can watch, play items from search results, or make purchases. These content restrictions are often also referred to as parental controls. You can restrict a variety of content and activities, such as:
Purchasing movies and TV shows
Playing movies or TV shows purchased in the Store based on content ratings
Playing content identified as explicit
Blocking playback of items from search results for content identified as explicit
To set or override restrictions, you must enter a passcode.