Photos

If there is an untitled folder in iCloud Drive and there are massive photos in it , and in system preferences > iCloud > the photos box is turned as on , the iCloud Drive and desktops and documents box is checked , syncing will start .

If you open finder and www.icloud.com and drag and drop those photos from iCloud Drive to iCloud.com an error will be shown for duplicate photos .

Inspite of saving photos in finder > iCloud Drive save in iCloud.com by setting https://support.apple.com/en-in/HT204264

And its preferences https://support.apple.com/en-in/guide/photos/pht5156cc968/4.0/mac/10.14

Don't waste the iCloud storage space in iCloud Drive see https://support.apple.com/guide/icloud/what-is-icloud-drive-mmd0b4a7f5e8/icloud

Note : you can right click on the untitled folder ( with all photos inside it ) , and move to bin and empty the trash .

You could but you would have to remove those photos to a computer, then move them into iCloud Photos, and after delete from iCloud Drive.

https://www.youtube.com/watch?v=WzN-0dJlPg8