Deleting photos and videos

Any iOS backup you have already created will not be affected by your subsequent actions on your iPhone.

But note your question is very unclear. For example, we have no idea where your photos are housed. Perhaps, for example, you already have them on your computer, in which case what you do on the iPhone is irrelevant.

Hello, If you delete a photo from your phone in the photos app it deletes it from iCloud and all of your devices, as far as I know, if you have a previous backup before you deleted them they will still be in the backup. When your iPhone backs up it backs up the current state of the iPhone and the things you have selected to backup, any other changes as far as i know will not be included in that backup.

Have a nice day!