If its key location.
Where your story takes place?
Is it in the past or future?
what's the history of the place? Who built it? Is it new or old? Who lives there? Whats it used for?
I think about this things.
I have an idea about where my story takes place and how it looks. Doing some concept sketching, the idea will get clearer.
"what the story needs,"I think it means if chapter one of your story takes place in a dojo, that means your story needs a dojo. You can go from your head and what you want the dojo in your story to be. Or if you want it to be a genuine dojo look up references, do drawing studies, read about dojos.
Have fun with it.