Can’t export photos from iPhoto library to desktop on MacBook Air

MacBook Air, M1, 2020, Sequoia 15.3.2.

After 5 trouble-free years, suddenly I cannot export images in my iPhoto library to the desktop.

I also cannot pull images stored in files on the desktop back onto the desktop. They show a cloud next to the title--I assume that means they are "in the cloud." But I can't drag the icon to the desktop or to an editor to work with it.

[Re-Titled by Moderator]