Hi There,
Khan academy has a large section that offers insight about college you can ask questions in the community etc. provided in the link below
https://www.khanacademy.org/college-careers-more/college-admissions

If you are an international applicant then the necessary requisites are:

1. High School Grade Point Average - known as the GPA.

2. Standard Test scores - including TOEFL, if your first language is not English, SAT, ACT, SATII, AP.

3. Extracurricular activities

4. Letters of recommendations from your high school teachers and professors from universities.

5. Essays depending the universities that you are applying for.