Yes, Comio S1 does have support for Jio VoLTE also. You will be able to use Airtel VoLTE as well.
Yes, Comio S1 does have the fingerprint sensor.
No. Comio S1 does not have dual rear camera. It has single lens camera with 13MP resolution.
Comio S1 is equipped with latest Android 7.0 Nougat.