Prior to Civil 3D 2018, this was the process of importing a point cloud and creating a surface in Civil 3D: Creating a Surface from a Point Cloud in Civil 3D
Due to the complexity and sizes of LIDAR (point cloud) data, processing the information within Civil 3D has become quite a task. To ease the stress of this process on Civil 3D, the ability to import points directly into Civil 3D was removed, and Recap Pro was introduced into the workflow. I’ve broken it down into two steps and two videos.
If you need help filtering out the data so you can use only the ground data you will want to read this blog: Filtering a Point Cloud for Surface Data in Civil 3D.