Which tool to use depends on your habits. The biggest difference of pen tool is that it has preview mode. Open the preview mode, you can easily preview the line while drawing it, and know the shape of the line after the next point is drawn. When drawing a symmetrical style diagram, you can first find the center line, first draw half, and then copy and paste the mirror image to get the other side of symmetry. This is just an idea. There are many tools and methods in CorelDRAW that can be made conveniently and quickly.