Not yet: editing blocks, hatches, splines, ellipses and the layouts (paper space). These are shown and stay unchanged in your DXF. A DWG does not open yet: save it as DXF in your CAD program. In the file, a dimension becomes separate lines and a text. Everything stays on your own computer.
You draw at full size in millimetres. The paper and the scale set the drawing frame and the height of text and dimensions.
This drawing has changes that have not been saved yet. Do you want to save them as DXF first?