How to Root your J3 with SuperSU
USB DEBUGGING MUST BE ON. It IS on the DEVELOPER OPTIONS…(JUST GOOGLE IT IN ORDER TO GO TO THE DEVELOPERS OPTIONS)
ps. make a back up….
Get your phone on fastboot by pressing The Power Button, Home Button and Volume Down Button at the same time.
Next, press download using the Volume Up Button and connect your phone to your pc using your usb connector.(IS a must that you use the usb port at the back in order to work properly!!!)
Flash the twrp-3.2.3-0-j3lte.img.tar using ODIN TOOL in order for you to have a TWRP REcovery.
4.Then, press the Power Button, Home Button and Volume Up Button in order to go on twrp recovery.
5.Lastly, Install The SuperSu zip …
Your J3 2016 now is rooted…