There is a variety of Operating Systems that can be used on a Raspberry Pi, and there is also a number of ways to install the OS onto an SD Card. In this tutorial we explore the two main ways to get the recommended Raspberry Pi OS (previously Raspbarian) installed and running on your Pi.
The first option below is to use the Raspberry Pi Imager application to install an image of the Raspberry Pi Operating System onto your SD Card.
The second option below is to use the New Out Of Box System (NOOBS). Most likely you would use this method if you have purchased a kit and it came with a pre-loaded SD Card, but you can also download NOOBS and put it onto a clean SD Card yourself.