How do get into car racing? like start a career and everything?

At 16 the first thing you need to do is work on your career, hopefully a good one as racing is quite expensive, Doctor, Lawyer, Politician comes to mind, or maybe a famous actor or musician, I know Steve McQueen did it, didn't work out all that well for James Dean. he was actually on his way to a race when he got smeared all over the road in that little Spider, but that's another story, then there's Michael Jordan, he owns a NASCAR truck team last I heard, so don't rule out becoming a star athlete.. But if you can only achieve Mechanic. plumber, production worker or bank teller, the chances are you'll just be able to afford a hobby in auto racing, if you plan to work at McDonalds the rest of your life your in way over your head.

first thing you will need is MONEY and lots of it. and also having a name - think Bruno Senna in formula 1 (decent but living of ayrton his uncle on his mother's side so changing your name counts) i think pretty much everyone starts of in basic karts (assuming track racing) and works their way up. there is always national/regional championships in every country. touring cars i think you could start in a low class in something like a fiat punto but karts will let you know if you have a chance of competing.