How to integrate json database into API?

Hi there! I need to implement ai assistant based on GPT API on the website, and for its answer, it should have the ability to check JSON data (it looks like a JSON object with a lot of “filters” that allow it to search some content on the website), and to suggest these filters to the user according to it needs. Which of the options covers my needs, assistants or fine tuning…? I see similar questions but they are dated like a previous year, so I hope there are more modern solutions was made this year. Thanks!