Turn on parental controls for an existing user
A managed user is someone whose account you manage using parental controls. To make someone a managed user, you can create a new user with parental controls enabled. Or, convert an existing standard user account to a managed user by following the steps below.
Choose Apple menu > System Preferences, then click Users & Groups.
Click the lock icon
to unlock it, then enter an administrator name and password.Select a standard user in the list of users, then select “Enable parental controls.”
You can’t set up parental controls for administrator or sharing-only users.
If you want limited access for a user on the Mac, but don’t want to add that person as a user, set up a guest user account that you manage with parental controls. For more information, see Set up users, guests, and groups.