Navigate to (or the Library tab) and tap Trash (or Bin). Touch and hold the photo you wish to save.
To recover deleted photos from Google Photos, your first and most reliable step is to , where deleted items are temporarily stored for up to 60 days if they were backed up. how-to-recover-deleted-photos-from-google-photos
How to recover permanently deleted photos from Android phone Navigate to (or the Library tab) and tap Trash (or Bin)