The tutorial demonstrates how to set up authentication and authorization in a GraphQL API using Apollo Federation and Express. It covers the key points of implementing JWT-based authentication with Express middleware, integrating it into an Apollo Gateway API, and adding permissions-based rules with GraphQL Shield middleware in an accounts service. The process involves several steps, including installing dependencies, setting up the gateway API and accounts service, creating a login mutation to obtain a JWT, verifying the JWT using Express middleware, passing the decoded JWT to the implementing service, and applying permissions-based rules with GraphQL Shield middleware. By following this tutorial, developers can create secure GraphQL APIs that protect their data while still allowing authorized users to access it.