For this you need a Minimum of 12500 points, to buy the necessary doors around the map.
Once all the subsequent doors have been opened, make your way to the Poop Deck
and use the travel pad that will take you to the Forecastle
, once at the Forecastle use the travel pad there to go back to the Poop Deck
When back at the Poop Deck make your way to the Mid Deck
part of the map, use the travel pad in the Mid Deck and you will be brought to the Engine Room
turn around under the water and make your way to the Boiler Room
which is where the next travel pad is located.
Go through the travel pad in the Boiler Room and you will be brought to the Grand Staircase
run forward to the area Millionaire Suites
and go through the travel pad.
Once on the other side you'll go to an area called Provisions
. Once inside the Provisions area go forward to the Engine Room and go up the stairs
on the left side of the room, and the next travel pad will be on your right.
Go through the travel pad near the top of the stairs and you'll go to the area called the Boat Deck
. Run from the Boat Deck back to the Forecastle (Spawn area)
to get to the Cargo
area. Go through the travel pad in the Cargo area it is directly in front of you under the water.
Now you will be teleported back to the Boiler Room, from here leave the Boiler Room and go across the Engine Room and you will see another door on the opposite side called the Turbine Room
Go through the travel pad inside the Turbine Room which is under water and you'll be teleported back to the Cargo area, and you will get the achievement.Call of Duty: Black Ops 4 I Know a Shortcut Guide
I hope this helped, thanks again.