The world is tough so you need to be tough as hell if you want to survive in this crazy world. Grab your gun and get a car to pursue your dream. You might get in trouble, but who cares as what only matters is that you fulfill your dream.
Get into a fight, the guy that you kill will drop a money. Pick it up and you can get your first mission. You can kill lots of people before you go on your first mission. Make lots of money form killing people because you are going to need lots of it to buy your first mission.