Workstation for CAD; 3D print WFH for Alzheimer's caretaker

I'm a 22-year-old stay-at-home caretaker of a parent in the early stages of dementia -- just a few days ago, I woke up to said parent waking up from a nap to tell me to turn the stove off, as it had been turned on while I was asleep, they forgot about it, and went to sleep themselves. So, I clearly can't be away for eight hours a day at a conventional job if I can't really even be asleep for eight hours at home. I did try, but nobody took me on.

So, instead, I've decided that at-home manufacturing (of a variety of things, though starting small) using 3D printing, and selling files for others to print is my best avenue. There's a problem with that: CAD is actually fairly intensive, and my years-old laptop with a failing keyboard (the enter key has long since stopped working) won't do. I've assembled a few parts over the years for a desktop workstation, but the bulk of the system's cost is still unaccounted for, and won't be for as long as I can't hold down a job. I need $2,500 to finish it up (motherboard, graphics, and storage).

For the manufacturing side, I plan on being as financially responsible with it as possible, hunting for deals where I can -- but a setup still isn't cheap. I think I can bring it down to $750. That's for a basic but still professional setup with enough to get started, and doesn't account for tax and shipping. There's some extra padding in there for any unaccounted for costs, anything leftover will go towards the workstation to choose the best parts I can within that budget.

And with animation, I admittedly do still need to learn, but I do plan on doing so, and have some experience with 2D animation -- though I plan on doing 3D.

Examples of my work (all in Blender, but I am learning FreeCAD as well):

Stretch goals:

Notice: please only donate if you're in a position to do so -- have a stable income and, ideally though not a requirement, have already donated to something more worthy. I'm going to be okay in the immediate term, but long term is where my future is in question, whereas there are people who need help right now.