In the Select tool, right-click on the object and click drag an area to select all the Nodes in that area.
To deselect, hold the Shift key down and when you hover over a Node and the pointer changes to up/down & left-right arrows, click the Node. This is a node at a time.
Shift-click is a toggle of the Node selection.

To avoid adding a Node, check neither end line Node is selected. If so, just press the Tab key.

Acorn