Now, more directly addressing OPs concern, one issue for me is pulling my door shut as I leave, and later realizing I had left my keys on the table, so now, I look at my keys in my purse to make sure I see exactly where they are.
In a sense, you need to do the same. Make sure you have what you need before you start out.
However, in this case, I would back up even one step further. Do I even want to leave the house? Maybe it is raining, and I want to wait. Maybe I have no money, so going to the grocery store would be pointless, even if I am very hungry.
You mention university a lot, but that is as far as you ever get. I have to wonder if it is something you really want, or if it is something others make you feel you want.
You have been given many tips and suggestions about assessing your talents and interests. At this point, you might as well decide to become a stripper. It doesn’t really matter, because you won’t give it a try anyway. It would at least be something you could practice alone at home.
I do have one idea you might find interesting. Here is a link.
This guy tells at the end he does classes online for making devices.
Check out the video and see if you care about learning some skills from this guy.