Puzzled351 wrote: In order to free up space on a MAC for more photos I have deleted several older photo albums.
When you deleted albums, did you see the warning window that said that deleting albums does not delete the albums' pictures?

Albums are just lists of pictures. so deleting an album deletes the list, but it doesn't delete the pictures that were on the list. Is this possibly why your Library size didn't change?
When pictures are deleted, they can be viewed for 30 days in the Recently Deleted view.

You can see that Recently Deleted has a trashcan icon. After 30 days the pictures there are removed forever. Before that 30 days, you can permanently delete them if you are in a rush. If the Recently Deleted view isn't shown in the Photos sidebar, then there aren't any "recently deleted" pictures still there.
So if you just deleted the albums like your post says, then you would have to go to the Library view and find those pictures. The Library shows all your pictures in the order they were taken. Another place to look is in Recents which shows all your pictures in the order they were added to the Library.
Or if they had things in common, you may be able to use a search for those pictures.