Duplicating a layer is not the same as making a copy of the source data.
Duplicating a layer
When you duplicate a layer, QGIS creates a second link to the same source file. Any edits you make to the duplicate layer are made to the source file. Any layers that link to that same source file will also have those changes.
To duplicate a layer, right click on ...
If it's the KML type, then that's the FME format attribute kml_name. You have it exposed in the reader, but then you need to connect it to something in the writer for it to get written.
Best solution is to use Manual for the output schema and add a new attribute (such as kmltype).
Then use an AttributeManager to rename the incoming kml_name to kmltype on ...
If you right click your layer in the table of contents, you can choose to Join data by spatial location. Alternatively, you can use the Spatial Join tool.
Actually, FID is not an official shapefile term, but refers to the row number in the unsorted table. Since Esri originated the format, calling this an artifact of arcgis is rather strange. Being a row-number, it is not stored in a column of the attribute table (DBF). The row number is used to tie the row to a specific shape. FID can be seen in QGis when ...