How to delete Photos and iCloud images without affecting Photos folder on MacBook Pro?

There are two ways to operate Photos-- a Referenced Library and a Managed Library. (A Referenced Library is very rare. The default is a Managed Library). You probably have a Managed Library, but you should check at Photos' Settings>General:

If "Importing: Copy"is checked, then good-- you have a Managed Library. A Managed Library holds copies of your pictures that were made when they were imported. The pictures in Finder folders aren't used. (They aren't referenced.)

In a Managed Library, deleting all the pictures in Photos would not affect any pictures outside of the Library. If you are syncing with iCloud Photos, and you look at iCloud.com to verify that all the same pictures are there, then deleting all the pictures in Photos will also delete all the pictures at iCloud, com.

If I were you, I'd first make a copy of the Library and put it someplace else on your Mac or, better, put a copy on an external drive. Also, I would not delete the pictures in the "Recently Deleted" view until a day had passed, and I had seen that all the pictures were also in "Recently Deleted" at iCloud.com. And I'd double check those Finder folders. Sometimes what you think see is not what the computer sees.

With all the pictures in "Recently Deleted," when you delete those, all the pictures in Photos and in iCloud Photos will be gone forever. A day after you're absolutely sure everything worked as planned, you can trash the Library and the copy of the Library, if you want. If you ever open Open Photos again, it will create a new empty Library.

What do you think?

If you use "Optimize Storage," then the full sized originals are stored at iCloud, and some of the originals may not be on the Mac until you need them. Nonetheless, if you delete a picture in Photos on your Mac, that picture, in all its versions, will also be deleted from iCloud.com.

If you have a Managed Library, then everything that Photos uses is inside the Photos Library package. If you are concerned, then you could transfer your picture folders from Pictures to Movies, maybe. Or better, copy them to one or two of your external drives.

When I import pictures from my Nikon to Photos, I first put them in Finder folders inside a Nikon folder in Pictures. I then import them from the Nikon folders to Photos, and I also copy the Nikon folders to an external drive. I then have 4 copies of every picture-- in Photos, in Finder, on an external drive, and on the original SD card. When the SD card nears full, I copy the whole thing to another drive before reformatting the card. You can't be too careful.

Cool. And no problem-- no schedules here!