Complete all test Exams
First you have to investigate the fire station, then follow two exams you have to complete.
Complete the Physical Exam
Head to the final exam site
Physical Exam – Running High
Go to the marker on the map (Charleston Herald building, south of Flatwoods), in the building you have to go up one floor and activate the terminal. Before you start the exam you should make the area a bit safer, kill all the super mutants. If you do not, it can happen that you die in the exam or you can not make it in the given time (3 minutes).
If you have activated the terminal it takes a few seconds, then you have to press the red button. Then go straight and follow the arrows! When you get to the place where you have to jump down, do not get irritated by the arrow in the house, jump down and keep going left.
As soon as you have pressed the second switch, you have to go back and press the first switch again. You have three minutes for it.
Exam #2 – Bernie
When you have completed the first exam, the final exam, which is located further south, will be at Belching Betty. This destination is also marked on the map.
When you get there, talk to the robot Bernie and go to the machine, put on the fire armor ( Fire Breather uniform and Fire Breather helmet).
Now go out and open the door to Belching Betty Mine, inside you have to activate the terminal to open the door to the mine. Now the exam begins, you have to go deep into the mine and activate the emergency beacon. Some enemies are waiting for you, use the anti-burn training pistol!
Once you activate the emergency beacon, return to Bernie, then go to the fire station and regsitrate, quest finished!
Credit-
https://games-guides.com/all-guide-list/fallout-76-into-the-...