Setting Up JBL T450BT Bluetooth Headphone On Debian Stretch

I have a JBL T450BT Headphone, which I thought it should work out of the box, unfortunately it didn't. My laptop connected to it but was not getting the stereo output (or High Fidelity Playback) in the headphones. I found a Debian Wiki for Bluetooth Headphone or A2DP (Advanced Audio Distribution Profile). It says to …