New tool_call API, and how to use it

Hey,
I’m using the chatCompletions API, and i’m trying to use function calling both for fine-tuning and basic conversations. i would love some clarification, or even a link to the right docs, as there is a lot inconsistency between the cookbook, API docs, and some of the posts here. My main questions are:

  1. What is the right way to incorporate tool calls in chat history?
  2. What is the right way to fine tune for function calling?
    I tried the cookcook, forum and docs, but honestly its just a mess
    Thank you for your help