Pairing ipad air with keyboard

Perhaps this support page will be helpful with troubleshooting and resolving the problem:

Pair a third-party Bluetooth accessory with your iPhone, iPad, or iPod touch - Apple Support

Is that an Apple keyboard?

Shouldn't be this case, contact its manufacturer support team and ask them about compatibility with your iPad model.

Regards

Giulio

So, it should be compatible with your device.

Are you having problem trying to pair it with your iPad Air? What happens when you try?

Have you put it in discoverable mode?

Giulio