iPad Pro / External Display

iPad Pro is not currently capable of offering an “extended desktop” experience - such as that to which you may be accustomed on other computing platforms. The multi-tasking “Split Screen” feature, native to iPadOS 13.x, is something else entirely.

Your iPad can drive an external display using AirPlay - or via HDMI (and appropriate adapter where needed) - but neither can re-scale the iPad output to match the native resolution of an attached monitor.

I hope you find this answer to be of some help to you.

If you are referring to the new SideCar feature of iPadOS/Mac, then this feature is intended to “extend” the Mac desktop onto the iPad - not the other way around.

There are also some iPad Apps in the App Store that provide some external connectivity options for PC and Mac (such as Duet and Duet Pro). These can be expensive - and have mixed reviews.

Here is a third-party comparison of some of the options - including a detailed look at SideCar.

https://thesweetsetup.com/apps/best-app-for-using-an-ipad-as-an-external-display/

I hope this proves to helpful in guiding you to some of the available solutions.

To be clear, an iPad with iPadOS installed can be used to provide an extended display from a Mac, to the iPad, using the Mac Sidecar feature. What you can’t do is extend the iPad display to the Mac from the iPad.