How To Retrieve Deleted Photos On iPhone
Accidentally deleting a photo on your iPhone can be a frustrating experience, especially if you’ve selected multiple photos you were intending to share, and instead, you’ve now deleted dozens of them. AsApplepoints out in a support document, recently deleted photos don’t instantly get wiped from your iPhone — rather, they go to a Recently Deleted folder within the Photos app. That folder contains any photos, videos, or screenshots that were deleted within the last 30 days. Beyond 30 days, your photos, videos, and screenshots will be permanently deleted unless you have iCloud Photo Library off and a recentiCloud or iTunes backup.
There are a few edge cases where you won’t be able to retrieve deleted photos. For example, if you accidentally deleted a photo that somebody else sent you in a text thread but never actually saved in the Photos app, that photo is gone forever. In that case, you could try and ask the sender to resend the photo if they still have it, however.

Retrieving deleted photos on your iPhone
Photos, videos, and screenshots — regardless of whether you deleted them on your iPhone, iPad, or Mac — all go to the Recently Deleted folder within the Photos app (viaApple). As long as you have iCloud Photo Library enabled, that folder will be synced across all of your Apple devices, making it easy to get back content you didn’t mean to delete as long as you do so within a month or so. To access the Recently Deleted folder:
Note: With iOS 16 or newer, you may be asked to enter your passcode or authenticate with Face ID orTouch IDin order to access your Recently Deleted orHidden folder. To turn off this requirement, head to Settings > Photos and turn off “Use Face ID.”

Permanently deleting photos on your iPhone
Likewise, you may want to permanently delete photos on your iPhone without having to wait 30 days for them to be automatically removed from the Recently Deleted folder. Unfortunately, there’s no way to automatically permanently delete your photos when you first delete them, so you’ll need to keep going back into that Recently Deleted folder and deleting them as you go. Fortunately, the process to do this is very simple:
Of course, permanently deleting a photo means you’re able to no longer get it back. Once you’ve confirmed you want to delete the photo, it’s gone for good, so be sure that you really do want to erase the content forever. If you have iCloud Photo Library enabled, that photo will be gone from all of your devices. If you don’t have iCloud Photo Library turned on, you may be able to recover your permanently deleted photos from a recentiCloud or iTunes backup.