Want to learn about cars?

I love cars and I recently started looking at big tech schools like uti and Lincoln tech but they are too expensive. My actual career goal is somewhere in the medical field like a PA. But I'm really interested in cars and would love working on them and having the knowledge to repair them plus it would be cheaper to fix my own car which is a 67 Honda so it has a lot of problems. There's a 26 week program called Pennsylvania technician training institute that is 12k but it's good compared to 32k from Lincoln and they offer state inspection license and 2.5k of tools. But I'm wondering if it would be a smart move to do if being a mechanic isn't my main career goal.

I've went into repair shops and tried to get free work or just be mentored and they don't want to bother with me because they are "too busy" to teach or let inexperienced people in.

If you have the means to work on your car. (like a garage at your house) then I would suggest the best education is reading books… And doing your research on the internet. Save your money for the education that you will need for your career path.
it'll take you a LONG time of doing your own repairs to make up the 12 grand course cost.

lots of people learn by doing. And you have the car to do the work on so you just start looking up how to do… Whatever job it is that you need to do. And you might even need to look up how to do it on a newer Honda and then just go and play around with your car to figure it out.
If you don't have the space to work on your car. Then there's even less reason learn it. As you won't be able to do your own work anyways.

Your 12 grand would be better spent on a newer used car so that you can tinker with your older Honda.
Experience is the best teacher.