Does iPad 11pro use Mac OS

Welcome, Blueduck239, to Apple Support Communities!

The various Operating Systems (OSs), for the various classes of devices (Macs, iPads, iPhones, iPods, watches, etc.) are all given their own names, to help distinguish between their intended purposes.

So, no. The iPad Pro does not run macOS. It runs iPadOS.

As for the heritage of the various OSs, and how their code-bases relate; that is a far more technical question, and fraught with incomplete information, since Apple has shared little, in such areas.

No, it uses iPad OS.