To build a ChatGPT-like SMS chatbot using the OpenAI API and Twilio Programmable Messaging with Python, users need an OpenAI account, a Twilio phone number with SMS capabilities, and Python installed. They also need to install necessary packages such as Flask, python-dotenv, and Twilio's Python Helper library. A .env file is created to store the OpenAI API key securely. The chatbot application is built using Flask, which creates a web application that receives incoming messages from users via SMS. The application uses the OpenAI API to generate text based on user input, similar to ChatGPT. After setting up the environment and installing necessary packages, users can run the Python Flask app by executing `python app.py` and test it by sending an SMS message to their Twilio phone number.