Download iCloud Photos as a JPEG (or original format) rather than a ZIP file on a PC.

I'm not a photography professional, so I'm no sure what a screenshot is. I take photos using the camera. I have the camera set to capture in the most compatible format, which normally is .jpg. To see if I could understand your comment, I went in and changed the camera capture to the high efficiency setting. That would use the HEIC fomat (iPhone 13 Pro, IOS 17 with current updates). Saved a couple photos, then went to icloud photos to download them (I am using a Windows PC.) I go to Icloud.com, then select photos. I then followed my procedure above to download single photos. I did find an even easier way, if you click on the photo, there are 3 dots in the upper right corner. Click on them and you get the choices I talked about above. Attached a picture here. You can see them in the bottom photo. The choices are the top photo. If I choose Unmodified Original, I get a single photo, .heic if my camera is set for it, or .jpg, if my camera is set for most compatible. If I choose Highest Resolution, it will zip the photo, even if just one. It will be a huge .dng file if the original is .heic or .jpg depending on the camera setting. If I choose Most Compatible, I will get a single .jpg photo. It will convert .heic to .jpg. This is how it works for me to get single, unzipped .jpg files on my equipment. Just FWIW. Tom p.s., the lines in the photos are artifacts from taking photos from my computer monitor.