This tutorial teaches how to deploy a serverless function using DigitalOcean Functions and Twilio SMS. To start, users need to create a free Twilio account, obtain a Twilio number, and set up a DigitalOcean account with doctl version 1.82.0 or higher. They then create a namespace and connect to it, initialize a new function project, and rename directories and files to align with the purpose of the scheduled SMS function. The `project.yml` file is updated to include environment variables for Twilio authentication and deployment settings. Users add external dependencies in a `package.json` file and deploy the function using the doctl command. Environment variables are set up, and a `.env` file is created to store sensitive credentials. Finally, users can test the deployed function by making requests to its URL, which should send an SMS with a motivational quote to a predefined number.