Scorpion5,
Welcome. What you are looking for is a wall niche object - to cut the hole / recess into the wall - for both the bookshelf and the recessed panel look.
Using one of the standard wall niche objects in the library (window/door tool), the partial hole will be cut in the wall. You can then add the shelves and other woodwork with the slab and wall tools (etc)... our re-size a bookshelf unit from the object library and push it into the hole created by the niche object.
The recessed panel would require a custom niche object. The Help describes how to create this using the slab tool. Alternatively, you can create a cutting mass that you subtract from the wall surface. The easiest way to create the mass is with to use the Morph tool in a section/elevation view of the wall, where you can draw the rectangles for the panels... then switch to 3D and push/pull them to the desired thickness and move them into the wall and using Solid Element Operation subtraction from the wall.
A couple of many ways of doing it...
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