If you're new, rest assured that narratives becomes easier with practice. Marketforce shops rarely have much narrative; you might try them.
One "trick" in common usage is to paraphrase the question. This "pads" your word count; just a tip. I'm so loquacious I often have to delete some narrative, because I run on and on and on.... For example, the question is "What color is the back wall?" You want to answer "White". I suggest your reply could be "The back wall is white." An even more observant shopper might state "The back wall is eggshell white, with a detailed crown molding running across the top, which is also white".
I hope this tip is helpful.