Nintendo Switch Manual page 37

You can set a limit to how long the console can be
used each day. You can also decide what happens
when that time runs out - will a notification display
on the screen, or will the user stop being able to
play the console for the rest of the day?
You could work out what sort of rules you'd like to
set together with your child.
Set restrictions on gameplay features
Nintendo Switch features can be restricted based
on your child's age.
The features that are restricted differ depending on
which of the three levels you set: "Young child",
"Child" or "Teen".
For example, selecting "Child" restricts games
rated for ages 13 and up, as well as features such
as posting screenshots on social networks and
communicating with other users within a game.