Career in dental industry

Hello I am 18 years old and am considering a career in the dental industry as a dentist`s assistant. Do you know how to apply for that role and what is expected of you? Things like do you have to be a standard of cleanliness or wear a uniform, where do you study, do you study in a college or at a dental practice?

Unfortunately I don`t have much in the way of useful education, I did GCSE music maths and English language all got a 5 in them but I doubt any are useful for this profession.

Any advice?