New to Business – Where Should I Start?

I come from a science background and have recently decided to start my own business. However, I have no formal knowledge of business, finance, or marketing, and I’m feeling a bit lost on where to begin. For those who have started a business (especially from a non-business background), what were the most valuable things you learned early on? Any books, courses, or resources that genuinely helped? Also, what mistakes should I watch out for? Looking for practical advice from those who’ve been through this journey. Appreciate any insights—thanks!