You don't need a degree to start a business. You only need a degree to work for other people's business.
Honestly kelvin, you are not cut out for business at the moment. You do not have the entrepreneur mind yet. If you do you would have instinctively find out what business is on your own instead of asking strangers on what course you should take. An entrepreneur mind is not something schools can teach. It's something that people argue is innate, or to some extent, can be trained by reading widely and being observant. You see what service/good is lacking, and you innovate or improve the things that will make society better.
I am an entrepreneur, started my first business when i was 17. Now 28, I don't earn big bucks, but i do know how tough is it to start a business in a ultra-globalised Singapore. It's even tougher now with the prevalence of internet and social media, together with the monopolisation of corporations like
NTUC and Shengsiong.