The Parallel Lines/Elements function in the Tools menu allows you to copy lines or elements in parallel.
The following image shows a polyline whose copy is offset outwards at a distance of 10 mm.
Offset Distance
Specify the distance you want to copy the lines or elements.
Line/element list
Select the line/element in the work window to which you want to create a parallel.
You can then specify the offset direction with the mouse. You can check the new line/element in the preview.