A variety of options exist for pursuing a career in astronomy. If you want to become an astronomy researcher, take as much math and physics in high school and college as you can. If you enjoy these courses and do well in them and maintain your passion for astronomy, you can then do graduate work at one of the many universities that offer Ph.D.s in astronomy and astrophysics. Ph.D. astronomers work for universities, observatories, NASA, and other research centers, although competition for the best jobs can often be fierce these days.
Even if you don’t pursue astronomy all the way to a Ph.D. (which takes 4 years of college and at least 4 years of graduate school), you can still become part of the astronomical community in other ways. Many astronomy enthusiasts become science teachers in middle and high school, work for a planetarium or science museum, or do public outreach in astronomy. — ANDREW FRAKNOI