There are many great resources out there, and I was planning to use codeacademy for coding, and khanacademy for fiance. Which subject would better suit me.
I know nothing about either one, and I'm 17, and in school.
The answer to this question really depends on what your goal. If it's something you're looking into as a possible career, you probably won't be able to do much with finance until you have at least a bachelor's degree. On the other hand, coding is something you can learn fairly quickly and begin making money within a short window. There are plenty of opportunities for building web sites or mobile apps.
I don't see why you have to choose one over the other.
High school students take algebra, biology, history, and literature all in one semester.
When you are studying online, you could spend a week with one, and the next week with the other and keep alternating like that.
Unless you have aptitude for coding you will be competing with every child out of school, who all want to be programmers.