What do I need to do for admission?

Great to know you are heading in the right direction. I too faced a similar dilemma few months back. Upon doing considerable research, I had found out that US universities require SAT/ACT, TOEFL/IELTS, AP tests, recommendation letters from your teachers, a bunch of personal essays, stellar grades and extra curriculars. Since you are already preparing for the SAT as well as TOEFL, I would recommend taking few Advanced Placement tests if available. Do remember that you will not be at a disadvantage if they are not available. Also do work on your grades and keep your GPA greater than 3.9 for ivy-league admissions. Extra-curriculars are also a vital part of your application and participate in all opportunities available. Since you are in 10th, this is the perfect time to explore your interests. By 11th, you should have decided what you are interested in and double down in that field and possible develop a spike too. Also develop a good relationship with your teachers and talk to them outside school hours. Overall, your essays, recommendations and extra curriculars should give a big picture about your personality. For more in depth information, do check out the other posts.