Based on the description it is only a setting that will help you to pick the right lens.
Change advanced camera settings on iPhone – Apple Support (UK)
On iPhone 11 models, iPhone 12 models, and iPhone 13 models, the camera preview displays content outside the frame to show you what can be captured by using another lens in the camera system with a wider field of view. To turn off this display, go to Settings > Camera, then turn off View Outside the Frame.
The created / saved picture does not contain the additional information, therefore you can not go back and restore information that was not captured.
Ralf