Art is an inherent ability. The only qualification you need is talent. However, if you do want to learn the technical side, you can enroll into different Degree Programmes, Diploma or hobby classes. If you are a gifted artist, then, you just need a little push in the right direction. For that you can simply get yourself into an art class and do a certificate course of about a week-3 Months. If you have got time and devotion, then you can do Bachelors in it and go on to pursue your Masters Degree. There is no end to the number of Certificate courses you can do, but, like I said before, if you have talent, then you don't need any degree. Your work will speak for itself.
