Warning: rooting phone or installing custom OS will void your warranty. The author takes no responsibility!
Go to about phone in settings
Tap on build number 7 times
Enable OEM Unlock
If phone doesn't show OEM unlock check out this article for possible solutions
Enter download mode by powering off device, hold power, bixby & volume down, when device vibrates let go of power.
At this point you just need to follow the onscreen directions
Press and hold volume up
In case you need to reinstall/unbrick your Samsung handheld. 😊
Good luck. 🤞
Note: you may need to manually reset your phone after unlocking bootloader! Check this tutorial for more info