Note: You can use iCloud Photo Sharing only with your System Photo Library.
Choose Photos > Preferences, then click iCloud.
Select or deselect the iCloud Photo Sharing checkbox.
Even if you turn off iCloud Photo Sharing on your Mac, you can continue to view and make changes to your shared albums using your other devices where you have iCloud Photo Sharing turned on.
Choose Apple menu > System Preferences, then click iCloud.
Click Set Up Family and follow the instructions.
After at least one member of your family accepts the invitation to view shared albums, a Family album appears in your shared albums.