I started another Blender course from Udemy called “Blender Character Creator”. The course assumes no previous experience so I have been pretty much just watching and taking note of things as they come up. I skipped doing most of the basics and created a biplane for the train world.
Instead of manipulating a box I animated a biplane. I still need to figure out how to get the propeller to spin.
I continued watching the DIY Engineering. The course had moved on from support structures and concrete sailboats to radio controlled balloon and rubber band powered airplane.