As far as I know there has never been a step 3 as shown above.

You drag out the base, then pull up to create the height and that is it. To add the divisions you go to the channel box, select the polyCube node and enter the subdivisions in in width, height, and depth.

You can highlight all three or any combination then holding the middle mouse button scrub left or right to increase or decrease them.

But I don't think it's ever been part of the interactive creation itself.