Ask HN: Planning to pursue physics degree without academic background

I don't have any higher education. My CS degree is half baked and I am 31. I was not in a great place in my early 20s (or anywhere throughout my 20s) to finish my degree, but always managed enough to work as a software developer. I am now moving onto high for my area paying job in consultancy in devops space, which I am stoked about, but...

I always had fascination with maths, but I was never good at it. I don't know how to study maths, or how to study at all. I know some algebra, a bit of limits but trying to tackle calculus left me frustrated.

I am really interested in physics, specifically thermodynamics and mechanical engineering.

I need some advice how to proceed.

I took some time to create a schedule around studying. I learned about study techniques (questioning, repetition, spacing, taking breaks, etc). I bought Spivak - Calculus (3rd edition) some time ago and moved my way through Foundations chapter a few years earlier, but exercises got really overwhelming pretty fast. I can do first few in every chapter, but struggle soon after. Is this normal for this book?

Now to complete my plan I have two things lacking:

- Mentor

- Study groups

While I can follow a textbook through a lot of grinding and suffering, but I feel like somebody with better understanding would be a great resource.

Same for study groups. If I am confused by an exercise, would be great to ask somebody who worked through it. I am lucky if Stackexchange has a similar question.

Now to be accepted to university, I will have to pass screening math test, which involves basic calculus, algebra, trig.

Which brings me to my original question: does it make sense to hop on a university program? That will get me to learning physics, provide support and have access to like-minded people. On the other hand, if I get good enough at maths to be able to pass the screening test, maybe I'll be able to move to physics by myself.

Does trying to find a tutor in my area make sense? Or online? Does anyone have experience with self-guided learning or with online tutor?

Any advice will be much appreciated!