Set up Find My on Mac
Before you can share your location with your friends and find your devices and items, you need to turn on Location Services and Find My Mac. You can do this when you open Find My for the first time or later in System Preferences.
Turn on Location Services
On your Mac, choose Apple menu > System Preferences, click Security & Privacy, then click Privacy.
If the lock at the bottom left is locked , click it to unlock the preference pane.
Click Location Services on the left.
Select Enable Location Services, then select Find My in the list of apps.
If you don’t see Find My, go to System Services in the list of apps, click Details, then select Find My Mac.
Set up Find My Mac
On your Mac, choose Apple menu > System Preferences, then click Apple ID.
If you don’t see Apple ID, click Sign In, then sign in with your Apple ID or click Create Apple ID (if you don’t already have one).
Click iCloud in the sidebar.
Select Find My Mac, then click Allow (if asked) to allow Find My Mac to use the location of your Mac.
If a Details button is next to Find My Mac, make sure you turned on Location Services and Find My in Security & Privacy preferences.
For details about privacy and how you can control what information on your Mac is exposed, see Guard your privacy.