I am interested in fashion design

Some colleges offer fashion courses, though if you want to be taken seriously in the field you generally want to have gone to an art school that specializes in fashion. Starting your own label is an incredibly difficult thing to do, most fashion students work for big labels for some time before branching out on their own. The art school I went to(not for fashion, was for game design) had about 1/4 of its campus dedicated to fashion.

To answer your first question, Etsy and registering your label's name as a trademark might be good places to start. The rest of your questions can be answered by doing research.

Always follow your dreams. If you wanna go into fashion, do it! You can even start out small in some community colleges offer fashion courses. Get a feel for things

A suitable clothing name for you would be "spoiled again"..haha