Hi @L_Pinkivy welcome to Zwift forums.
You might want to use the Apple TV keyboard app on your iPhone. Previous discussion about that on this thread.
Bear in mind that the Apple TV still has a hard limit of three Bluetooth signals that it can pair to at a time. If your Zwifting hardware broadcasts more than two (power, controllable, cadence, heart rate, etc), use the Zwift Companion app to pair all these things.