Help with "bookworm" by Nuru Karim

Hello! I would like to see if anyone can help me finish modeling the bookworm project by NUDE architects. I have gotten up to the point where I am able to create the undulation and I have flat surfaces with no massing but I want to add the shelving to the model, can anyone assist me by any chance?

I followed a tutorial provided by HowToRhino on Youtube but it is incomplete, https://www.youtube.com/watch?v=1W1GRGpiqlg&list=RDCMUCwImuwbI4lKk544-FS7A2Yw&start_radio=1&t=1169
this is the link to the video just in case!

many thanks!

How to ask effective questions