When you're trying to write a creative it can be as simple as trying to flesh out that idea to any stimulus.
so let's say you're faced with this stimulus
"Looking outside was out of the question"
You could then just get any plot to try and bring that not belonging aspect to life.
e.g. could be a story about a young girl who is struggling to come to terms with who are her true friends.
But remember, most of the time don't just end it at not belonging, if you do you miss out a core element of the rubric, you must show that maybe she actually ironically belongs more through not belonging to a certain group.