Fine tuning and embedding use case

Hi, I have one question. I’m using OoenAi gpt4 model API for a application that I’m building. My question is, I wanna make something like figure 01 humanoid robot style bot, so in such case I want it to be richful on some specific topics only for say only Foods related. So, in such case does fine tune the model is good or knowledge base embedding or both can be used in this application.

Also, is there any best way or docs or tut that shows you to do such modeling and get the model to use it on application in practice to understand how does it work?