If I understand correctly, you deleted a video and you want to get it back. I would recommend you read this article, it explains how to recover from the Recently Deleted album.
Get your photos back
If you accidentally delete a photo, you have 30 days to get it back from your Recently Deleted album. When you recover photos and videos, they go back into your All Photos album.
- Open the Photos app and go to the Albums tab.
- Open the Recently Deleted album and tap Select.
- Tap each photo or video that you want to keep.
- Tap Recover and confirm that you want to recover the photos.
If you're missing a photo or video, you can try these steps to find it.
Thank you for using Apple Support Communities. Have a good one.