Entrepreneurship and investing are not the same. So what are you asking for? Investing is more about seeking yield, while entrepreneurship is more about the actual organizing of capital, labor, and other means of production to maximize that capital return. Sometimes the entrepreneuer and investor are the same entity/person, often it isn't.
So to answer both questions:
1) You learn investing skills from patience and knowing how BAD human beings are at picking winners. So, for maximum returns, you park your money in a low ER total market fund and forget about it for 30 years.
2) You learn entrepreneurship skills from trial and error, and not outsourcing tasks early in the process. Starting and managing a business is 80% drudgery (paperwork, accounting, tax strategy, legal, liability mitigation, and regulatory compliance, etc...) and 20% "American Express TV commercial fun" as I call it. You pretty much throw pasta at the wall, see what sticks, see what doesn't, and retool/do it again. Keep your circle small in the beginning and grow slowly.