Walk around the tutorial and you can start the game with a boss, brewery, speak, brothel and safehouse.
The early game simply send out your boss and solo the thugs, recon the city, and begin accumulating cash and an arsenal. It is easy to take out up to three with no problem but the gangs of five take a bit of planning. No gangsters mean you save several hundred dollars in expense per week for the first year or so it takes to recon the city.
The gangsters do level up over time so pick the ones you want long term. I hate buying cheap gangsters then firing them.
Then put your boss in a safehouse and sent your newly recruited gangsters out as a small strike team to earn their stripes. It is very easy to do, and most bosses grant economic bonuses when parked in their HQ.