What is the first step in starting a food consulting business?

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have some one with extensive food system experience running it.

Learn about food. Take some classes. You have to know what temperature refrigerators and other equipment needs to be at. What temp sterilization takes place. Etc.

Get a library card and spend some months years learning reading about the industry locally.
Spend some months reading learning about the process of getting started locally as it varies greatly.

Experience in the food industry. What sort of Consulting are you planning to do?