A model must be specified. Lots of code out there is obsolete.
This other topic at 13 days ago has bespoke Python code for uploading, initiating fine-tune, and monitoring train progress.
It coincidentally uses the same model.
Your own .jsonl file name, and a custom short prefix for model name of your own, shall be edited in.
Epochs parameter is 1 for a “light” training at lowest expense, while 3-5 is a good starting point (if not deleting that parameter to allow OpenAI to decide how much money to spend.)
A helpful AI model or OpenAI’s quickstart can tell you how to prepare a Python execution environment, with your OPENAI_API_KEY stored as an environment variable and automatically used.