An operating system needs to be installed onto the Micro SD card before inserting it into the Raspberry Pi.


Skip this chapter if the Raspberry Pi already has an operating system installed.

Raspberry Pi Imager is a quick and easy way to install the Raspberry Pi operating system to a Micro SD card from a computer or laptop.

Browse to the Raspberry Pi Imager site and download the version that matches the computer or laptop’s operating system ( When the download is complete, launch the installer program and follow the prompts to install the Raspberry Pi Imager.


If the Windows operating system prevents the application from launching, click on More info and then click on Run anyway to install the Raspberry Pi Imager.


Insert the Micro SD card into the computer or laptop’s SD card slot. If the computer or laptop only has a full-size port for SD cards, use a Micro SD card adapter.


Upgrading the Raspberry Pi OS to Debian Bullseye will cause some features to not work, so it is recommended to continue using the Debian Buster version.

In the Raspberry Pi Imager, click CHOOSE OS -> Raspberry Pi OS(other).


Scroll down to the end of the newly opened page and you will see Raspberry Pi OS(Legacy) and Raspberry Pi OS Lite(Legacy), these are security updates for Debian Buster, the difference between them is with or without the desktop. It is recommended to install Raspberry Pi OS(Legacy), the system with the desktop.


Select the SD card you are using.


Click the WRITE button.


The Imager will overwrite any files already on the SD card. If the SD card has any files, back up these files before clicking Yes.


After the Imager completes installing the Operating System on the SD card, click Continue to complete the installation.


Now insert the Micro SD card with the system installed into the Raspberry Pi.