You can delete photos and videos:
Do one of the following:
From the list of thumbnail photos:
Do one of the following:
If you automatically back up photos to your Google account, you have some time to recover deleted items. When you delete a photo or video, it’s moved to the Trash in the Photos app for several weeks, before being deleted forever.
To recover a photo or video:
If you don’t back up photos to your Google account, to maximize use of your phone’s internal storage space, there’s no undo. Once you delete something from your phone’s storage, it’s gone. You can try using a third-party app to recover recently deleted photos or videos.
If you’re having issues, try these troubleshooting steps.