Downloaded iCloud photos not appearing in Wallpaper app on iPad

I downloaded a number of wallpaper images. The images go to my iCloud but none are found in my wallpaper app. I don’t know how to add them. I tried copying them to a new folder on my iPad but I still can’t get the wallpaper app to see or find them. How can I get these images to be seen through my wallpaper app?

[Re-Titled by Moderator]