What do you mean? You can always use a distro like Steam OS (or any other Linux distro) on any x86 PC and still use a mouse and keyboard. Or use a Steam Deck and plug in a mouse and keyboard.
A steam deck with a mouse and keyboard is kind of horrible, I have tried that. And maybe things have changed, how well does Steam OS do as a primary OS? I might look into it again.
You can use any Linux distro and install steam on it? I really don’t understand the issue you’re having. It works perfectly on pretty much any modern mainstream distro.
Their questions are actually pretty straight forward, I really don’t understand the comprehension issue you’re having or why you feel the need to add the incredulous response.
Do you find the need to call people out like this in everyday conversation?