Hi, I am new to Blender for modeling, have moderate Solidworks experience and am trying to modify a STL and do not know functions to get to my end goal. I am looking at making a cavity in a flat surface that will be the exact geometry of the rounded item. This will create a nest point so that I can 3D print both separately and be able to place one item into the other to hold it. I am just starting work on this now and files are in STL format.
Also, if I want to manual augment the surface of a STL object to add say a vein, ridges, or extra surface contour, how can this be done? This is for a Sci Fi model, have image in my head just having issue getting finished product onto computer.