Apple’s iCloud Shared Library lets users automatically share photos and videos they’ve taken with others, so no one misses a single photo from a trip or event. You can create a Shared Library with up to 6 people (including yourself), and at any given time, all library participants have full control over what gets shared and when it gets shared.
How to Stop Sharing Photos Between iPhone and iPad, Mac or iPhone
If you no longer want someone to share their content in the Shared Library or have access to their content in the future, you can remove them from the Shared Library, provided you are the creator of the library.
When you remove a participant from your shared library, they will have access to everything in the shared library in their personal library, as long as they were in the shared library for more than 7 days. If that participant was in the library for less than 7 days, they will only receive the photos and videos they added to it.
You can remove people from your shared library by following the steps below.