Impossible to make a duplicate photo in Photos

With a new computer with an "upgraded" version of Photos, it is impossible to make a duplicate photo in photos.  You may actually make a duplicate photo but YOU don't know WHERE it is, and the new Photos program cannot find it.  

The only way to make a copy of a photo in Photos is to take the image OUT of photos, (because the new Photos program is, unbelievably, unable to make copies of photos) open it in Preview, duplicate it there and then drag the copy back into Photos, which will come in at a different date from the original (copies should be next to the original) 

-- Having to take a photo out of Photos just to make a duplicate, demonstrates another way the folks at APPLE are unconcerned about ease of use of their products, and must have some kind of sick delight at knowing all the new customers are going crazy trying to make a new version work with the ease of the previous version.  

[Edited by Moderator]