when samsung will give nougat update in India

The fingerprint is working slow then ever and I had by the phone before 2 days and the fingerprint is too slow

when I am Connecting my wireless earphones to j7 prime by Bluetooth so after sometime the connection is lost e.g. when I am watching a movie or a video on j7 prime it say your wireless earphones disconnect. so what the problem white prime?

can galaxy j7 prime can update to grace ui or 7.0

can I get update of new ui grace ux on my galaxy j7 2015 edition and 7.0 nougat