mini displayport to macbook air

Sure. You just need an appropriate cable or adapter.

Here's one: https://www.apple.com/shop/product/HN8B2ZM/A/mophie-usb-c-cable-with-mini-displayport-connector

and another https://www.apple.com/shop/product/MMEL2AM/A/thunderbolt-3-usb-c-to-thunderbolt-2-adapter

sure.... try this: (link)

you'll also need a spare minidisplayport cable, which I'm sure they'd be glad to sell you. Very reliable, good prices and free shippng.......

that's it

john b