In the recycle bin or Recently deleted folder,deleted files such as photos or videos are kept for 30 days and then permanently deleted.

To keep track of the Gallery app on the OnePlus smartphone, individual files or the entire recycle bin can be emptied at once.

Note: After deleting the files, the data cannot be recovered.

Android 10 | OxygenOS 10.0
Step 1:  Open the  Gallery app
Step 2:  Tap on  Collections
Step 3:  Tap on  Recently deleted
Step 4:  Tap on  Delete
Step 5:  Confirm with  Delete
  1. Open the Gallery app
  2. Tap on Collections
  3. Tap on Recently deleted
  4. Tap on Delete
  5. Confirm with Delete

OnePlus Instructions