I want to start a snack brand. I am wondering if anyone is willing to share their experiences on how they went about it. I will not promote this

I have a lot of questions on how the process works. 1. How did you build your first recipe? Did you have to hire an organization with your initial base recipe to plan out the preservatives? 2. Did you outsource manufacturing or did you do it in-house? 3. What are the other processes I am probably missing? and what did each cost you? 4. Are there special terms in the industry that I should be aware of?