Before opening a restaurant, you should manage one first. Seriously. You can't learn everything in class. No class teaches you about how to deal with suppliers. No class teaches you how to manage staff. No class teaches you how to deal with customer complaints, negative reviews, etc. No class teaches you how to develop the best menu for your restaurant, how many dishes to serve, what sort of dishes will sell, how to price your dishes, etc. No class can teach you how to decorate your restaurant, which type of lighting, sound, cutlery, dishes, glasses, tablecloths, etc to use. No class will teach you about the insurance requirements for a restaurant.
Sure you can learn about accounting, cooking, advertising, employment law, food safety and marketing in a class. But running a restaurant is a lot more than that. Just watch shows like "Restaurant Impossible" or "Kitchen Nightmares" to see all of the issues and problems people have run into when opening restaurants.
I would recommend working in a restaurant and managing one for at least a year before you even consider opening your own.