What should i do in the next 4 years to be able to get into and Ivy?

I am a freshman in brazillian high school and I have currently started my journey into the ivy league world. I have completed the cambridge english proficiency tests and have a current gpa of 3.7. I will start IB classes next year. I have won the Brazillian Astronomy Olimpics in 1st place and have also won a statal dance competition twice. It is really hard to initiate research here, especially in the field of astrophysics. I will also be participating in a cheer competition in two months. I teach dance for kids in a really poor community. Is there something I can work on to improve my application? How?