Below are a couple of ideas of how to add shelving. Second pic - use a narrow bookcase and 3rd pic this would be on the wall. Add a floor lamp or a wall light. You could also pull the desk up closer to the bed and use a stool that slids underneath, so you don't have to be moving a chair..it will double as a side table. If more ideas, if you search Houzz photos re: trundle beds, it may also help.
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