When thinking about what university you may want to apply to or even thinking about a potential major, one tool that can be very helpful is to browse through some course catalogs.
Most universities now have their course catalogs online and you can see classes offered, pre-requisites by major, etc.
Some examples include:
University of Chicago The College Catalog
Boston University Courses Search
So start browsing and learn more about what your day-to-day classes at these universities would actually be like!