How do I get the magnifier out of Mirror mode on iPad Pro?

I, for one, have no idea what “mirror mode” means. This is not a term used by Apple. Perhaps you’re talking about a selfie and the iPad camera. Perhaps you’re talking about screen mirroring, although I don’t think a magnifier exists in that context.

Please be precise in your wording. What application? What actions have you taken to get to this quandary point? What choices are you offered?

I still have no idea what you’re trying to say.

Lundylou wrote:

When I open the magnifier appp it is using the selfie or rear facing camera.

OK, you’re talking about the Magnifier app. Here’s a writeup about its capabilities.

Use iPad like a magnifying glass - Apple Support

Great.

For other readers, if the camera icon is not visible, tap “Settings”, swipe up and find and add the “Cameras” entry.

Enjoy your iPad.