Assuming subjects and skills refer to book-learned knowledge rather than life experience: I'm trying to decide what to study in college or through MOOCs like those offered by EdX or Coursera or whether or not I should choose a business or a non-business major. I am trying to decide what to focus on. If I self-studied instead, I wouldn't have any debt from my degree but could still need a degree for other reasons. What specific topics are essential for entrepreneurs to know? For example, there's a lot to learn as a finance major and I'm not sure which topics would be relevant for entrepreneurship. I've tried thinking about it in other ways, for example: "What should a successful entrepreneur/CEO be able to do?" and tried to figure out which subjects will teach me the skills I'll need to achieve those goals.
One of my favorite resources is an Ebook on Audible. Critical Business Skills for Success by The Great Courses. It's 34 hours of value. Get an audible account with your first credit or two for free. Apply one of those credits toward this book. Some of he most valuable traits one can possess as an entrepreneur is an open mind, a love of learning, and unbreakable optimism.