Your Commercial Pilot License allows a pilot to accept pay for transporting passengers or cargo (when complying with FAR PART 91, 135, OR 121).
The license is required for other pilot positions such as flight instruction, banner towing, and aerial photography. The license never expires. The flight training must include operations in an aircraft with retractable landing gear, flaps, and a constant speed propeller (complex aircraft or a Technically Advanced Airplane-TAA). This training fine-tunes piloting skills. The minimum age requirement is 18 years.