Do not treat Civil 3D as "AutoCAD with extra buttons." Watch Autodesk University classes. Learn the "Object Hierarchy" (Surface > Surface Operations > Breaklines). It is a different logic, but once mastered, you will never want to go back.
In a team environment, one engineer works on the road alignment while another works on the storm drainage. They reference the same base data. If the road moves, the storm drain updates. autocad and civil 3d
The viewport is the "window" through which you view your design in model space. Do not treat Civil 3D as "AutoCAD with extra buttons
The engineer uses basic AutoCAD lines to sketch rough road alignments over the existing contours. Surface Operations >