A:AnswerYou should be able to see them in the “Find My” app if you have an Apple device (don’t know where to look if you use android) as long as you have them paired to your device you should be able to see it there
A:AnswerIf you have the aux cable that comes with the headphones then yes you can plug them in that way. Unless the plane screens have Bluetooth then you can absolutely connect via Bluetooth.