1) Even if your schooling was in English, you may need to still take the IELTS or TOEFL. Each school policy is different, but it is common for schools to require Indian students to show proof of their English language abilities.
2) On a related note, pay attention to your audience when crafting your personal statement. While you should feel encouraged to show off your culture in your Common App essay, be advised that many phrases and grammatical structures are unfamiliar to the American reader.
3) It is important to stay involved with extracurricular activities. It is common for students to drop sports and arts involvement when in the later years of their secondary school. While your grades are still a priority, American colleges have their pick of the litter when it comes to high achievers. They will choose the A student who is a student council president over the student who lives in the library.