Answer the question you selected for profile question 3 here (300 words):
My advice would be: read a lot and ask many questions!
Read books, magazines, and social media articles about science. The more you read, the more you will learn about what fields of science interest you the most and what are the major questions scientists are working on in this field.
Talk to your teachers, college students, graduate students, etc. Ask them many questions, they have been in your shoes and will be happy to help you succeed!