Once you jump out of the plane, you need to press Sprint to use the wingsuit. Glide towards the marked area. When you get close to the ground,, open your parachute.
You will notice several pirates on the shore, standing near the truck. There is also a cage with a tiger in it, which should be freed, so it can handle several of the enemies.
Go around the remaining enemies, so that you are behind the truck. After you kill every last of them, get into the truck and get onto the road to the right of the beach. At the road's other end there is the entrance to a village.
Enter the Crazy Cock bar and talk to the bartender. Then, approach the door at the other side of the counter and give money to the guard shown in the screenshot. Go down to the basement and take your place at the table. After you play a game, leave the basement through the door that Sam left through. After you watch the cutscene, follow Sam, to complete this mission.