I'm a high school student in India and I'd like to live in the UK. Which field should i choose so that i don't have to study again??

You could only obtain a job with an employment visa if you are fully qualified in an occupation on UK's shortage list. By the time you earn the requisite degrees, plus experience, to qualify, the shortage list will change.

Take a look at the current occupation shortage list; these are the positions that will get you a work visa. (If, of course, you can find a qualifying employer to sponsor it)

Oh