I'd suggest that at your age, you start with this as a hobby, and learn your lessons with a small scale operation before you decide to sink a lot of money into this. Look around at the web sites of small commercial operations; what are they doing to make their operation commercially viable? Do this as a hobby on a smaller scale, and see if you can first get to covering your costs, and figure out what scale you would need to turn a profit from there.
Also - it's wise to have a contingency plan. Get a good education that you can apply to a variety of tasks, so that you have solid, marketable skills if your business plan doesn't work out.
Nothing wrong with chasing a dream. Without that, not much would get accomplished. On the other hand, making a career out of niche agriculture can be very challenging. You'll need to study far harder with this than you ever had to in school if you're going to make a business out of it. As another poster already mentioned, if you're having to ask how many feet to an acre instead of tracking down that information yourself, you are a long, long way from being self-reliant enough to start a business. Not being mean here, just trying to get you to consider what mindset it takes to succeed.
I'm considering hobby farming to be my "retirement" plan, and I expect to spend years and years learning it and ramping up before I'm ready to bag my IT job and do it full time ... and then I'll probably end up working harder and longer in "retirement" than with my "desk job." ...