How do I start a business?

The devil is always in the details and this question has no details.

You need a product or service that you have super skills and knowledge about; a clear and reasonable plan for how you can bring business in the door consistently and enough money to survive long enough to put your plan into action. If the business involves selling a product, you must be able to buy the product at a low enough price to compete with the current competieion.

Whether you survive in business will not depend on how much you want to be there it will depend on whether the buying public wants you there. Before you make the move, you should have a specific idea of what you will provide the public that will make them want to deal with you over your competition. Don't think you will just open your door and the world will rush in. Going into business is more like jumping into a gang fight against a group of experienced fighters. You'd better know how to fight.