Build applications with GitHub Copilot agent mode

This is a GitHub Skills exercise teaching how to use GitHub Copilot's agent mode to build a complete, multi-tier application from natural-language requirements. Working from a preconfigured development environment, the learner prompts Copilot Chat's agent mode to build a fitness application for a high school gym teacher, covering presentation, logic, and data layers.

The exercise assumes basic familiarity with GitHub Copilot, GitHub itself, and general web development, and follows an earlier prerequisite exercise on getting started with GitHub Copilot. It is designed to take under an hour, with each step opening a new Copilot Chat session, and is set up by copying the exercise to the learner's own account or organization, after which GitHub Actions prepares the first lesson automatically. It is provided directly by GitHub as one of its Skills exercises.