None of my Bluetooth devices will pair with my new iPad Air

The most common issue is they are paired with a previous device and haven't been put in pairing mode to connect with the new device per the manufacturers pairing instructions.

The Related Article link at the top of this page, which brought you here offers suggestions you should try. But do make sure, if they are already paired with another device, that device is powered off and you have put your devices in Pairing Mode to connect with your new iPad.