The tutorial describes how to create an AI friend using Twilio Voice, Twilio Functions, and OpenAI's GPT-3 engine. The AI friend, named Joanna, will converse with the user in a human-like manner using synthesized speech. The conversation is handled by two functions: /transcribe and /respond. The /transcribe function listens to the user's voice response and passes it to the /respond function, which uses GPT-3 to generate a text response that is then converted to speech. The tutorial covers setting up Twilio Functions, OpenAI API keys, and caching conversation data to ensure a proper conversation flow.