pixels

The size of the camera sensor for a camera is fixed. That’s the maximum resolution available for the camera.

An iPad can use digital zoom (stretching the image on the display before triggering the shutter), and can also use different back-side camera lenses for photos. This zoom gets you “subjectively closer”, trading off for resolution.

Different iPad Pro models have different camera resolutions, and the resolutions of the front and back cameras usually also differ. The iPad Pro model and year requested that was requested above will tell us what the limits of your participation configuration are.

Within the Photo tool and other export tools for transferring files, you can select larger or smaller image file sizes, and these image sizes mean higher or lower resolution.

Usual means to transfer full-resolution images is with iCloud Photos (which is also available on Windows), or by connecting the iPhone to the Windows computer with a cable, and importing the photos that way.

Sending photos around by mail usually gets lower-resolution images, as the higher-resolution images require more storage, or sometimes much more storage.

For some related details: Transfer photos and videos from your iPhone, iPad, or iPod touch - Apple Support

If you're emailing the photos from your mobile device what setting are you using?

You'll need to give more information

Take with what?

Where are you seeing the image sizes?

Even 1000 is quite small these days.