What subjects/ courses interest you? Also you can always apply for something get into a university and change courses relatively easy so long as they are not highly competitive courses.at this
Previously at least my understanding was it was quite typical for students applying to creative arts courses to undertake a FAD course first, as it allowed them to develop and refine their portfolio for applying to degree level art and/or design subjects first and foremost. It also gave them the benefit of experiencing what it is like to do creative design and art work "full time" as such, as a lot of FAD students would've previously only done perhaps one or two A-levels in a creative arts subject, out of three.
FAD courses are free for students who are under 19 years of age on the first day of the course as I understand, as they are FE courses, not HE courses. However as FE courses, you cannot apply for funding from SFE to fund those (including maintenance loans etc). They are distinct from integrated foundation years which are built into an existing degree programme, as they are separate to any given programme and thus are accepted by and allow you to apply to a wide range of universities.