With Revit you need to think about what your desired final outcome is (in terms of documentation) and then discover the best path to get you to where you'd want to go. The trick is to find to what degree you want the geometry to give you your details vs 2d detailing. Small projects can be full of complex geometry, really large projects not so much. In my experience it's always better to start by keeping it as simple as possible and only add complexity as needed. You also need to think about how likely the design is going to change. Editing something you made in blinding state of creativity months later can lead to serious frustration/ running in circles.
So, a 6m deep shaft could simply be walls with a single floor or it could be a 125mm thick section arrayed up n amount of times over 6m. It could also be a number of other things but start by by keeping it simple, don't over complicate things if you don't need to.