Can I use my Mac as a second display for iPad Pro?

LotusPilot wrote:

A further option is to mirror your iPad's display wirelessly to a Smart TV or AppleTV box that supports AirPlay:

Use AirPlay to stream video or mirror the screen of your iPhone or iPad - Apple Support

If the Mac is new enough to support AirPlay to Mac, the OP could set it up as an AirPlay Receiver. The OP's iPad Pro could then use it like it was any other AirPlay-capable device.

Continuity features and requirements for Apple devices - Apple Support

Stream video and audio from your iPad with AirPlay - Apple Support

It appears that the OP has already discovered this ("right now I see I can mirror my ipad onto my MacBook") but wants the iPad to use the Mac in "extended desktop" mode ("i want to be able to have VisRef (ipad only app) up on one monitor and use procreate on the iPad itself").

I could be missing something, but I don't see anything indicating that an iPad can use an AirPlay display like that. AirPlay from an iPad to another device seems to be for streaming video, or mirroring, only.

While your Mac can be used as display for PC using proprietary hardware solutions - such as AstroPad Luna - your Mac can not be used as a secondary display for your iPad.

https://astropad.com/product/lunadisplay/

Your iPad Pro can, however, be connected to a computer monitor or TV using a suitable HDMI Adapter - or, if your iPad Pro features a USB-C port, directly to a computer monitor that supports DP or HDMI Alt Mode over USB-C.

Connect iPad to a display with a cable - Apple Support

A further option is to mirror your iPad's display wirelessly to a Smart TV or AppleTV box that supports AirPlay:

Use AirPlay to stream video or mirror the screen of your iPhone or iPad - Apple Support