I highly recommend it. There is soo much involved in running a business, and too many go under because owners had no clue on how to properly manage all the different aspects. Accounting, business mgmt. And even marketing is a good idea. Most community colleges offer night classes and it doesn't take forever either. I did it and I'm glad.
It depends on the size you want your business to grow to. If you want it to remain a candy shop, you need just some basic selling and customer handling skills. If you want it to grow into a stream of shops, then you need higher managerial skills to handle people and finances in your business and also permits for the goods and store.