Recovering deleted photos on Android or any other device requires patients and some presence of mind.
👉 After you know your photos are deleted first thing you should be doing is not do any task on the device that creates and deletes files on your device storage,
Because if you constantly doing task that writes the storage then there is less chance of recovering deleted photos as they are going to be overwritten by the system.
How data recovery works
you can read on Wikipedia data recovery
"Sometimes, data present in the physical drives (Internal/External Hard disk, Pen Drive, etc.) gets lost, deleted and formatted due to circumstances like virus attack, accidental deletion or accidental use of SHIFT+DELETE. In these cases, data recovery software are used to recover/restore the data files."
If deleted media was stored on SD card then the process might be little easy as you can take help of your PC or Laptop for recovery work.
For this remove SD card from the device
use SD card reader to plug-in the SD card to computer
use Data Recovery software any of the following
Recuva
Puran File Recovery
Disk Drill
Glary Undelete
SoftPerfect File Recovery
for more check source
If deleted media was stored on Internal storage then you need to take help of apps for data recovery
DiskDigger App
More Data recovery apps
If you used any gallery app that supports trash (recycle bin) feature then it can help you recover photos if you accidentally deleted the photos within those apps. look for trash folder in app to resotre the photos,
Prime example of this type of app is Google photos, Oneplus gallery, Mixplorer File manger,
Hope you will be able to recover photos from your device, do mention if you find any problem in recovering photos.
Source:
https://support.google.com/photos/answer/6128858
https://www.lifewire.com/free-data-recovery-software-tools-2622893