Movable shelves can connect each other with different height levels.
First of all,
1- I opened a new project template and saved it in my famigliamadre file.
2- After that i followed these steps new family>metric faced based
3- I created reference lines for my first square shape
4- I added parametrics and also materials (to add materials I followed these steps; family type>add>duplicated one of the material>changed the colors and choosed solid as a pattern.)
5- Also added parameters for the right/left sides
6- I saved this project as family project in famigliamadre
7- Loaded this project and placed it on workplane
8- To make a new part of the shelf I created a new family template and followed the same steps that I mentioned before.
9- To hang this shelves I needed to void some part of them (void extrusion tool)
10- After I added them as a parameter and material I also saved this project into famigliamadre file and loaded it into that project.I moved the parts on the first part that I loaded before.
11- To create the top part I also followed same steps and saved it in also famigliamadre file
12- Lastly, I created my final part ''wall''