From Paper to Unity

Hello,
I am (trying) to develop a 2d Platform game
I made sprite and animation using Spine
I made a sprite sheets to make platforms and a lot of script to make live my game.

Now my game designer, following this link How to design levels for a platformer – Dev.Mag , made a detailed layout of the demo level using millimeter paper

Now I am in trouble…I am trying to build into unity the detailed layout but I dont know how to proced.
Have you some hint or tutorial to explain how to translate form paper to unity into proper way ?
Thanks

You could scan/photograph the drawing, import it to unity as a texture, put it in the background then kind of rotoscope on top of it to place actual prefabs/objects?

Nice idea,
I will try

Thanks