If you are enrolled in a course, you must attend the first class or else the instructor can give your seat to another student. You must either confirm through your portfolio that the instructor has dropped you from the course or go through the process of dropping it from your schedule yourself through your portfolio. This is good information for you to know, especially if you want to check out another course that meets at the same time. You risk losing the seat that you do have.
If you are unsure about which level of course to attend, check out the course textbooks at Broadstreets Bookstore. That, in conjunction with reviewing the course syllabus, talking with the instructor when the course meets, and consulting again with your faculty advisor should help you make a decision.