You can apply to join a course with a flight training organisation to get your Commercial Pilot Licence CPL(H). You'll need the CPL(H) to fly helicopters commercially.
To get onto a training course, you'll need:
- 5 GCSEs at grades 9 to 4 (A* to C), including English, maths, and science
- to pass skills tests and a thorough medical assessment
- a minimum of 155 hours' flying time
The number of flying hours needed may be lower for trained aeroplane pilots.
As a first step, you could train for a Private Pilot's Licence PPL(H) which allows you to fly for personal use and build up your flying hours. The flight training school would assess your skills, and could ask you to take some pre-course training to prove that you have the level of ability and skills needed for commercial training.
Training is expensive and you'll usually have to fund it yourself.
You could also join the Army, Royal Navy or Royal Air Force as a trainee pilot.