We'll be using CircuitPython for this guide. Are you new to using CircuitPython? No worries, there is a full getting started guide here.

Adafruit suggests using the Mu editor to edit your code and have an interactive REPL in CircuitPython. You can learn about Mu and its installation in this tutorial.

Install the latest release of CircuitPython, version 4 (or higher) for your particular CircuitPython-compatible board. Follow the instructions here using the appropriate CircuitPython UF2 file.