Looking at his other projects, I think this guy uses VCarve, in fact, he may be a member here under another name or the Facebook group and may chime-in but this is the type of projects that VCarve excels at, it is also more geared towards artistic projects than F360. He mentions the price barrier which makes me think it is VCarve as F360 is free for hobbyists. Here are some of the 2.5/3D stuff I’ve done with VCarve.
You are having issues with F360, I can relate, IMO, unless you are very familiar with CAD, it has a much steeper learning curve than VCarve. VCarve is closer in look and feel to Carbide Create but much more powerful. Did you look at the intro videos I posted on F360 above? Before you get into 2.5 or 3D, you have to learn the basics of the software that is explained in these videos.