When I draw a line on my canvas there is a line on both sides of the node and no path

It sounds like you are clicking on the canvas, holding down the mouse button and dragging...this creates a node with handles. The lines you see on both sides of your node are its handles. You need to click on the canvas with the pen tool and then release the mouse button and move your mouse to another position on the canvas and click again. This will then create your path.