The only way I can seem to achieve this is to draw the full length line and then Split it at the required points. This can lead to accuracy problems. Is there a way to suspend the Line auto-merge function in LO so I can simply draw individual lines?
Do note that disabling auto-join will only prevent the line you are drawing from connecting to other existing lines. To draw what you have shown, you’ll have to draw a segment then reset the tool by hitting the escape key before drawing the next segment.