Where Can I Register/apply For A Summer Project/job In America?

Your best option is to apply for work in a summer youth camp. The summer camp culture in the United States is far more developed than in the UK (where it is still quite new), and as such you have much better options and will earn more money in America. Additionally, in most cases you will get free board and accommodation, on top of your salary. You can probably expect to earn around $400 to $600 every two weeks as a counsellor, and a little more as a lifeguard or activity leader. Most camps will start accepting applications in early December, so be on the look out and visit sites like this one towards the end of the year. Best of luck!