It's great that you're eager to learn—your background in data science actually gives you a big edge in understanding personal finance logically. I’d recommend starting with practical, proven resources like the Bogleheads wiki and the book “The Bogleheads’ Guide to Investing.” They focus on simple, long-term strategies that work.
The MIT Finance Theory course is solid, but it’s more academic and may be overkill for personal finance goals. Start with foundational topics: budgeting, saving, indexing, risk tolerance, and tax efficiency—especially in the EU context.