Generally speaking, you are not recommended to join. A lot of joining is for your money. If you want to make money, why don't they open their own chain stores and let you make money?
For example, if you want to open a hot pot restaurant, if you don't understand, you can work in a physical store first, and you can learn anything you don't understand. As long as the catering products are not too small, you can basically get the formula by some cheap methods.