The Crimson Fleet are an organized group of pirates that are one of the biggest threats to the Settled Systems. They were founded after a major jailbreak from the United Colonies over a century before the beginning of the game.
How to Unlock the Starting Mission
Instead of joining the fleet directly, you’ll have to become a member by going undercover for the United Colonies. This can be achieved in two ways:
Getting arrested in New Atlantis, some methods for this include smuggling contraband, stealing, or attacking a guard.
UC SysDef will recruit you to go undercover for them, say yes and you’ll be on your way to becoming a pirate.
How to Reach the Starting Point
Before joining the Crimson Fleet, you’ll have to meet with a UC commander to be debriefed. Go to your Starmap and navigate to the Sol system, above Alpha Centauri. In the system, navigate to the ship southwest of the star, the UC Vigilance.
Aim towards the huge ship in the middle of the fleet and press A to dock with it. After the docking animation, board the ship and you’ll find the security guard to start Dead Money.