Integrate ChatGPT Into PHP App Development

I have a lot of existing code that I am now trying to get ChatGPT to expand and effectively write more code that is plug and play. Seems to be a few challenges in getting ChatGPT to get the code to that point... (Budget: $10 - $30 USD, Jobs: AI Development, Android, API Integration, Chatbot Integration, ChatGPT, Mobile App Development, MySQL, PHP, Programming, Software Development)