Thanks for the feedback! So what I did for No6 was that I created a basic grid plane (with reference to my desired camera angle) and started drawing out basic shapes for all elements in the painting on top of that plane. For example, for the tree, I made a basic block-in of a cylinder in the right perspective (3 point) on top of the grid plane. On this, I started adding my details and the required twists and contours.
There’s a little imagination involved along with a clear knowledge of perspective in this, so practice drawing simple shapes from this angle. You’ll soon get the hang of it. Hope this helps