How remove photos from my iCloud for free storage

If you use iCloud for syncing photos you have to be careful. You remove them by deleting them. But in doing this it will want to remove them from all devices connected to that iCloud account. If you still want a copy of the photo, make sure you have put it somewhere that iCloud doesn't sync to. For example, I have turned off my computer's syncing to iCloud photos. Once I have a photo on my computer I can delete it from iCloud and know that the one on my computer is safe.

Delete photos on your iPhone, iPad, and iPod touch - Delete photos on your iPhone or iPad - Apple Support - "It's easy to delete the photos and videos that you don't want anymore. Just tap the Trash icon and you're done. You can also learn how to make space on your device and where you can get your photos back if you accidentally delete them."

"Before you delete anything, make sure that you back up the photos and videos that you still want. When you use iCloud Photos and delete a photo or video on one device, it's also deleted on all other devices where you're signed in with the same Apple ID."