Check the Gallery app’s Trash/Recently Deleted folder
Check Google Photos Trash or iCloud Recently Deleted
Restore from a cloud backup if available
Restore from a device backup on your computer
Check other synced apps or gallery backups
Use a file recovery app on the device
Connect the phone to a computer and scan storage with recovery software
Check the SD card with recovery software if the photos were stored there
Stop using the device immediately to avoid overwriting deleted photos
If needed, contact a professional data recovery service