I am trying to create this shape
but I am having some difficulty. I have tried to do it by first adding the loop cuts, then using Extrude Faces Along Normals (with Offset Even enabled), and then finally trying to delete the extra faces that are left, like this:
However, after doing this, I am left with only a large face that is selectable (I would expect that both of them would now be individually selectable). This is shown in the image on the left below. The only thing I can do from here is to start deleting many of the bottom faces and try to rebuild.
This seems like a lot of work, so did I do something wrong with the extrude tool? Any tips/guidance would be great.
(I don't want to use the boolean modifier, because I am trying to practice and learn how to use the other tools (extrude, etc), and get a feel for how to manipulate the mesh).