After you have everything set up to your liking, close out of the options menu and select Write on the main Raspberry Pi Imager window.

I'm going to assume that the majority of the people who want to set up OctoPrint will do so on a Raspberry Pi though, so my instructions are geared to installing OctoPi.

Follow these steps to setup OctoPi OS on your Raspberry Pi in a few basic steps regardless of your machine’s operating system. So what exactly is OctoPrint?