In pursuing my Business degree - it was required to take at least one finance course that covered: Introduction to concepts and techniques of business finance. Topics include organizational forms, agency relationships, financial analysis and planning, the capital formation process and capital markets, risk and return, time value of money, stock and bond valuation, and capital budgeting. *This is straight from my college course website.
It was not an easy class but I felt overall it is important to know. Depending on the college you attend- you can go online and search the catalog of classes and may even get to look at the exact syllabus prior to joining.
I would recommend taking the general Finance class first (as you will need this class in pursuing a business degree) and see if you like it before pursuing a Major in it. You can even sit in on a few classes on harder finance classes as well to see if you are interested. Or watch classes online through sites like Coursera: https://www.coursera.org.
Finance is a pretty broad area but most "Finance" classes will be about how money moves around the economy and businesses. Specifically, are you interested in learning about how businesses raise money they need to grow their business? How do businesses invest this money and what types of decisions they need to make along the way? Finance classes will involve a lot of math to calculate the cost and benefit of these decisions relate to how you raise and invest money.
I studied business in college. Our finance courses basically taught us two things: how to estimate the value of assets (including machinery, businesses, real estate, options, or whatever else you might want to buy), and how the modern international financial system works. That means we spent most of our time learning and practicing valuation calculations of various types, or reading case studies or articles about financial regulations and financial markets. We learned about the CAPM and the basics of portfolio theory. We learned about what options are and how to value them. We learned how investment banks make money and some of the terms used in the field.