Moving photos back to iCloud from Windows

For a long time I was archiving photos off of iCloud to save space in my iCloud account (saving them to my Windows hard drive and deleting them from iCloud). Now I pay for more iCloud storage and wanted to move my photos back so they'd be available on my phone. I found a help article that says all you have to do is copy the pictures to the iCloud Photos folder in Windows Explorer, but I don't think this is right, because my iCloud Photos folder has no images in it--they are all in subfolders (Downloads, Shared, and Uploads). Should I really be copying them to the Uploads subfolder (which is currently empty)? Or should I use the Downloads folder (which is full of all my iCloud photos)?

I'm also wondering if I copy everything that got downloaded when I archived (I downloaded zip files from the icloud.com website), will I still be able to view the live photos? I'm hoping that if I upload the jpg and associated mov files, Apple will still recognize them as linked.

Thanks for any insights!