how VC++ make code ? When are exclude library

Visual C++ does not make code by itself. You write code in editors provided by Visual Studio based on the problem you are trying to solve. There are editors that allow you to write code by drag & drop, like the Windows Forms editor, but ultimately you are the one who make the code written. After you finish writing you can build the code.

There are some common libraries linked to a project by default, you can use /NODEFAULTLIB to remove one or more libraries from the project.