Thanks. I definitely will teach myself some of the pre-requisites before registering in University. I need to prove to myself that I can sit down, take some course, complete the coursework + assignments + exams on MIT courseware, before committing anything that costs $$.

Math Academy is really all you need. 30 minutes per day is enough, though more time will mean faster progress.

You would still very likely need human input and help. LLMs will hallunicate badly on problems just a bit more difficult than the very standard ones (first-hand experience with math).