I have download and install esri plugin to autocad. can and how I will import shp file to Autocad?
I don't think ArcGIS for AutoCAD would help you in importing shapefile to CAD. You could do this in AutoCAD Map/Civil 3D. And in ArcGIS Desktop of-course.
If you only have simple AutoCAD 2012, and none of the above software, you could do this using spatial manager for AutoCAD. You could download the trial version from this site.
Spatial Manager™ - Download
Can you tell me how to convert from Cad to GIS?
You could use CAD to Geodatabase (Conversion) tool in ArcGIS.
CAD to Geodatabase—Help | ArcGIS for Desktop
In case, you are querying in context of AutoCAD, you could do it using AutoCAD Map/Civil 3D or Spatial Manager for AutoCAD.
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