Delete shared albums from iCloud for Windows
With iCloud for Windows, you can remove a shared album you created by deleting it. You can remove shared albums you subscribe to by unsubscribing.
On your Windows computer, open Shared Albums.
Right-click the shared album you want to remove, then choose “Delete shared album” (if you are the owner) or Unsubscribe (if you are a subscriber) from the shortcut menu that appears.
When you delete a shared album you own, it is removed from all your devices and the devices of all its subscribers. When you unsubscribe from an album, it is removed from all your devices.