How to put back button and exit button in you facebook app

YouTube Video Link :
https://youtu.be/6AueIBCKy3k
Via YouTube Channel : AboutURL "Hello" दोस्तों आपका स्वागत है हमारे YOUTUBE चैनल पे, ►Subscribe Our Channel ► Click on link Given Below ► ► Facebook: http://ift.tt/2BfziuY ► Twitter: https://twitter.com/UnboxingReviewm ► Youtube: https://goo.gl/iN4YWm ► Instagram: http://ift.tt/2zgcJVN LIKE | SHARE | SUBSCRIBE FOR MORE VIDEOS LIKE THIS THANKS FOR WATCHING! --ENJOY-- Please: Don't forget to SUBSCRIBE this channel for more Trusted & Awesome videos. DISCLAIMER: This Channel DOES NOT Promote or encourage Any illegal activities, all contents provided by This Channel is meant for EDUCATIONAL PURPOSE only.