Mirroring iPad on to MacBook air
Not sure if the iPads with USB-C can do this, but if you connect your iOS device to a Mac, you can mirror/record your screen with QuickTime Player.


Connect your iPad or iOS device to your Mac.
Open QuickTime Player.
Select File > New Movie Recording.
Click the little arrow to the right of the record button and select your iPad from the list.


After this, your iPad's screen will appear on screen. I think the floating recording window will disappear if you don't have your mouse over it.

You may have to trust the computer on your iPad or iOS device to get this to work. The aspect ratio will be preserved on screen, so a portrait iPad would be 3:4 and landscape would be 4:3.