.Saving/storing photos

No. iCloud Photos is a syncing service. Any photo you delete from a device where iCloud Photos is turned on will also be deleted from iCloud and from any other device connected to iCloud Photos. You can potentially reduce the storage space required on a device by turning on Optimize Storage. See: https://support.apple.com/en-us/HT204264

Apple does not currently offer cloud-only storage for photos. If that is what you want or need, you may want to explore 3rd party options such as Google Photos or Dropbox.

You don't need to delete the app. You can turn off iCloud Photos. But if you ever turn it back on, they will all sync to it again. See the following for information about turning it off on one device: Get help with iCloud Photos - Apple Support

But what happens if I just delete the photo app from my iPad and then later restore it? It seems that some of the space it takes up on the iPad are photos that I have actually downloaded. I want to keep everything in the cloud but need space on my iPad.Yes, they are already optimized but I have a lot of pictures in the cloud. Thoughts? I wouldn’t be deleting any pictures just removing the app temporarily.