Cupcakes need little investment. If you want to sell them work for a day, buy your flour, oil, milk, etc. bake them and sell them. That doesn’t require much patience.
If you want to sell furniture you’ll have to have a workspace, tools, and more expensive materials than furniture. It will take time and dedication to save for it.
If you want to sell cars you design. You’ll need wealthy investors. You’ll have to convince them and be persistent against rejection.
Everyone has to find the right version of business for themselves. And you may go through many of them in your life.