3DPrinting

I haven’t used it but there is also tinkercad

I will be blunt. If you are as bad at math and spatial reasoning as you say, then CAD probably isn't for you. You will always find it difficult and unrewarding. Design and engineering require a mindset you might not have.

As far as "cheap and easy and professional" CAD they ALL require effort to learn and money to gain entry for commercial versions. CAD is a skill and skills require effort to acquire. And it sounds as if you have no desire to put in very much effort.

For a CAD program to meet your want of cheap and simple, (professional means a lot of money and takes more than a few minutes of effort), look at TinkerCAD. It's free and simple enough that I teach that to 5th and 6th grade students well enough for them to make simple objects. Ain't nothing wrong with starting there and learning how to think about design and CAD before you might try and step into more demanding software.

I tried using FreeCAD 5 or 10 years ago, and it was painful. I had access to Inventor, so I used that for the limited work I was doing. Later, I heard of some build/pack/whatever that removed a lot of pain from the FreeCAD workflow, but I can't remember what it was called and I wasn't doing CAD work any more. Trying to find that led me to this, though:

Ondsel ES Look

Also, I found a video on YouTube that appears to go through the same steps. Here it is.

I'm not sure it that will solve your problems, but the 20 minute video should answer that question for you.

RS Design Spark?

I haven't used it in a few years but I remember it being alright for hobby stuff.

I use alibre, it’s a one time purchase

Also tinkercad. It's basic but honestly it works for most stuff I make for things around the house.

I'm looking for the same thing for electromagnetic FEA. Besides Ansys or Comsol, both of which are unattainable for hobbyists, there're really no options.

The problem is that Parametric CAD kernels are complicated and expensive. There are some recent open source efforts but they are slow going. Just look at how bad Freecad is after all these years to see how difficult they are.

I'm quite experienced with SolidWorks and have used both Creo and NX as well. I can't stand the likes of Freecad or Fusion because of that. Luckily I have access to the professional ones for my day to day modelling.

One option to look at is Solid Edge, they have a maker version that is free and it's a proper professional package many companies use.

Fusion is easiest to get going for 'serious' projects as a beginner.
I will use it while I can, or until an equal alternative is available. Nothing lasts forever.

Pirated inventor is good. Fully local, used by lots of people. Free when obtained on the high seas

Solidworks has a cheap maker version. You can save locally. It's always been shit, so it can't get enshittified /s.

Fusion 360 is free for non commercial use.

I got a 3d printer about a year ago and looked into CAD software and came to the exact same conclusion you just did. I ended up using Plasticity. I thiink I paid $150 for a year of updates. But there are still two major drawbacks: first is it's not parametric, as you said, but more importantly you can't import stls and edit them. You can export stls, but you have to make them from scratch. You can technically import an stl but it's impossible to edit. Oftentimes I find a design online but I want to tweak it to my purposes but I can't do that.

I'd love it if Free CAD had a better UI. It's just so frustrating and hideous to use.