Help! Connect IpadPro to Marantz AV7005

Go buy the APPLE Lightning Digital AV Adaptor

Ipad - plug in the Lightning AV Digital Adaptor ,
Plug in the HDMI cable Into the adaptor and the HDMI cable out to AVR

The simplest version of connectors is if it fits, it works. Apple combines audio and video into one USB-C connector. Or Lightning, whatever it is on iPad, I forget. Anyway point is you go from that to whatever is on your Marantz. If it fits, plug it in, select the input, see what you get.