The geometry will automatically be shown in the graphical display window once the import process is complete.
Use the mouse buttons to rotate the model to approximately as shown below:

As is typical of STL data, the triangle definition is relatively poor and coarsely faceted. The surface is closed and manifold however, and as such, can be used as a the basis of a surface remeshing operation in order to improve the triangle quality. Before this can be done, the boundaries and feature curves should be defined.