dxf to idw conversion is typically searched by users that need to transfer technical designs and other 2D CAD content from standard DXF files to Autodesk Inventor. IDW format is used to store 3D content, so this is pretty much 2D geometry to 3D conversion, which typically requires manual redrawing and not something you do with a single click.
Inventor supports import of DXF format just fine, so this the most obvious option how to achieve this. But perhaps other software with Inventor format support might be of help as well.
Updated: September 6, 2023