File menu > Open > DXF file-type.
When you do: File menu > Open and select the .DXF file-type, you add a DXF-element to the Assembly-Tree.
The DXF-element is the container for the DXF-Drawing.
You can then link that DXF-element and DXF-drawing to a CAD-Line.
To show a DXF-drawing, do two(2) steps:
STEP 1 : File menu > Open > DXF file-type
STEP 2 : Show the DXF-Drawing
When you save a DXF drawing in your original CAD software:
•Save the DXF drawing as Release 1, or as near to Release 12 as possible.
•If you use 3D CAD, use Hidden Lines Removed before you save the DXF drawing