Inactive Tutor answered 08/30/19
It depends where your photos are located.
if within the photos app, select your pictures and click on the Image menu in the Photos menu bar and choose Hide [number of] Photos, or press Command-L.
This will place your images in a special album called “Hidden,” which is, itself, hidden by default. To show or re-hide the Hidden Photo Album, look for that option under Photos’ View menu.