i think you have to have the ability to raise an inordinate amount of finance that is supported by a huge insurance policy incase your project is a flop.
You can only become a producer or director after gaining many years experience in the movie business. That can be fairly difficult in the UK because our film industry is much smaller than that of the USA. (Junior film staff can't normally get employment visas to work in Hollywood. Only the 'big name' producers, directors and actors, are allowed to work in the USA. The US authorities have to agree that the UK citizen is doing a job which can't be done in the same way by a US citizen).