Is there a science course that I have to take in order to graduate ?

If I am planning to major in finance, do I have to take a science elective in my first year ? I am asking because if there is, I would just take an AP science course to skip that.

Yes you would need to take a natural science, which you can get out of with an AP science

You need a 4 or 5 on the AP exam to get out of the science requirement.