I have recently been admitted to MBA school. Let us say I do complete my MBA and I am sure I will learn quite a bit in the process. But if I want to start a company or bootstrap a business, and that can take many years, how do I feed my family while this is happening? What do I do for cash flow? Do you advise that I put these plans off until I can answer that question for myself at a future point in time? Do people generally take on consulting assignments or something like that?
Here's the thing, you haven't really said, "Yes!" and your concerns about how you will make money belie this. See the Preideation Stage of the Bootstrap Map.
There are many aspects to the journey and most focus on the external - product, customers, organization, funding, etc. But the greatest battle is internal - as Krishna counsels Arjuna in the Bhagavad Gita!
My excuse, many years ago, was my green card. I told myself I couldn't start my company unless I had. However, once I made the commitment, things started falling into place and the green card (which at the time was 2yrs away) showed up in 4 months! Every activity except doing your business is procrastination - or another way to say it is that all it does is prepare you to say "Yes!" There is a pervasive myth that you need to learn business skills before you start you business. If that were the case, Microsoft, Virgin, Dell and many others simply wouldn't exist. Great bootstrappers are lifelong learners who pick up the knowledge, skills and resource they need as they go along the journey. They know that the key is simply to get started and doing so is the only thing that truly begins the entrepreneurial journey. Awakening to yourself and developing your unique passions and talents begin at the Matrix stage.
With the inner commitment, you will easily resolve the money issue by massively reducing your burn rate (you need MUCH less than you think you do), asking your family members to help create consistent cash flow, taking on consulting in the area of your interest, etc. You will figure it out and take full responsibility for doing so. And every action will lead to the unfolding of your adventure and success.