Help needed!

I currently live in the uk and am hoping of coming to the US to work as a physician. However i am studying at college in uk and then i was planning on getting a degree in an English medical school. I realise i will probably have to do some extra work to be able to be a licensed doctor in the us, however. I am not sure how long i will have to study in the us and where. Please could somone help me answer these questions and possibly give me some advice. Thanks in advance.