The Steam Deck is a handheld gaming computer that runs a Linux-based operating system called SteamOS. The machine comes with SteamOS 3 (code name "holo"), which is in turn based on Arch Linux.
Although there is no SteamOS 3 installer for a generic PC (yet), it is very easy to install on a virtual machine using QEMU. This post explains how to do it.
Exactly what it says.
https://www.osnews.com/story/135060/running-the-steam-decks-os-in-a-virtual-machine-using-qemu/
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