Having a commercial license means you can get paid to fly, typically doing jobs like like sight seeing tours, banner towing, crop dusting and requires a minimum of 250 hours of flight time. to qualify for an airline job you need a minimum of 1500 hours. Most people build time instructing but that requires a separate certification on top of a commercial license. Instructing also sucks because you’re usually an independent contractor getting no health insurance/benefits and only get paid for the time your student is paying the flight school. Student paying $60/hr for ground instruction and $200±/hr in the airplane? The instructor is getting paid $25/hr
Banner towing sucks because while towing the banner you fly at the slowest possible airspeed without stalling nearly the whole time. (Aerodynamic stall, nothing to do with the engine) The airplane controls are much, much less responsive due to less airflow over the control surfaces (ailerons, rudder, elevator) Its exhausting compared to flying at typical cruising speeds the airplane likes to fly at.
The best flying jobs are for major airlines but you’re away from home 4 days a week staying in a new hotel every night so it sucks if you have a family. When you first start out as a new airline pilot with your 1500 hours you work for a really shitty regional airline getting paid like 60k and do 3-5 different flights per day which is exhausting because you have to do the most labor intensive and stressful parts multiple times per day rather than just flying across the entire country once and only doing the planning, takeoff/departure, and arrival/landing once. Also you’re not home 4 days a week.