Your first task after the cutscenes is to get the keys to the stolen armored van. Enter the other room where the key is located and you’ll find a dead guard and another gagged one, on the chair. You can either leave the alive one alone or kill him.
As for the other body, you can carry it and feed it to the gators to unlock your first trophy in the game. (Bon Appetit!) You can use the same method to hide bodies if there are gators lurking in the water, especially in swampy areas. Take note that gators can instantly kill you as well if you happen to be swimming in the same water as them.
Get the keys on the floor, then exit the garage and enter the armored van’s driver’s seat. You now have to drive it to the Federal Bank in the Downtown area, about 2.4 KM away. You have to drive responsibly here to avoid getting the attention of cops or civilians from calling in on you.
Take advantage of the temporary road signs that will appear as you drive; this serves as your GPS and will point you to the right direction when you have an objective activated. Once you’ve reached the bank, slow down and turn to the entrance to trigger another cutscene.