I am using on NXT with android 7.0 can I get this option in my mobile

how to use WiFi calling in model: on NXT , android version 7.0

I am using galaxy on nxt (j7 prime) with latest updated as nougat I have one issue after update is if my phone goes offline it's not coming back online where we are back to city now putting my phone to flight mode then back to normal almost I am wast...