You can lock and hide your photos in your iPhone and iPad devices that has ios 16 and more. If you're currently ios 16 and more tap this link for learn that how can lock iPhone photos and videos in photos app on iPhone.
For old versions of ios you can use the method for lock to photos on iPhone or iPad
Here's how: You can lock your photos on an iPhone using the built-in feature called "Notes".
• Go to the "Notes" app on your iPhone or iPad
• Tap to "New Note" for Create a new note
• if you will take and lock new photo Tap on the cam icon to take a photo to the note.
• If you will hide or lock a photo that you have already it in your photos; go to the photo in your albums and copy it and back to note and paste it.
• Or add a photo to your note from photos with add button
Lock the note that you saved your photos;
• Select "Lock Note" from the list of options.
• If you haven't already set up a password for Notes, you'll be prompted to create one. Follow the on-screen instructions to set up a password.
• After setting up the password, your note would have been locked, and the photo you added will be secure.
Now, whenever you want to view the secret photo, you need to password or face ID or touch ID you created for Notes.
We can also lock other notes that contain special information or photos using by same method.
