Hi,
Let your cursor on the little red rectangle, Visual Studio should purpose you some ways to fix this.
Nothing to do with COM,
- Document class defined in Autodesk.AutoCAD.ApplicationServices namespace from AcMgd.dll or AcCoreMgd.dll
- Editor class is defined in Autodesk.AutoCAD.EditorInput namespace from AcMgd.dll or AcCoreMgd.dll
- Transaction class is defined in Autodesk.AutoCAD.DatabaseServices namespace from AcDbMgd.dll
You have to reference these DLLs (AcCoreMgd.dll only for AutoCAD 2013+) and import these namespaces.