You don't need any training but if you have none you may get in trouble from bad management right away.
Most community colleges offer courses in small business management.
If you have no idea about running a business then having an accountant may help if you can afford one.
You need to understand overhead and cash flow and government regulations. Does you city or town require a license? Should you have insurance? What kind? What are your obligations to employees?
You should really be able to have enough cash on hand not to require making a profit for at least a year otherwise things could go downhill in a blink of an eye.