Set up users, guests, and groups
If your Mac has multiple users, you should set up an account for each person so each can personalize settings and options without affecting the others. You can let occasional users log in as guests without access to other users’ files or settings. You can also create groups. You must be an administrator of your Mac to perform these tasks.
Add a user
Choose Apple menu > System Preferences, then click Users & Groups.
Click the lock icon