Sympathetic vs parasympathetic
What sort of help are you looking for?
A clear heading first. Move or remove the skeleton etc. Next be clear about the message you want to convey. The graphic of the pathway through the nervous system to Sympathetic / Parasympathetic Divisions is the focus of this poster, and it is unclear. Redo the path and text to make it clearer, so you’re happy with it, then add pics and backgrounds.
Simplify simplify simplify
Too much information, too many colors, too many fonts, too many things vying for attention.