Choosing an enterprise(s) for your farm business is not a linear process. It will involve examining your goals, skills, and passions; market demand; and your available soil, climate, and infrastructure (including proximity to slaughter facilities if you're considering livestock). You may feel at times like you're going in circles, as these things are all inter-dependent, but the idea is to keep gathering information and refining your ideas until you settle upon one or more that seem feasible.
This process builds on the resource assessment and values/mission you began writing in the Goals, Skills and Resources tutorial - make sure you have at least begun to establish these fundamentals before moving on.
With this foundation in place, the process of choosing an enterprise can be thought of like a pyramid. Each time you climb the pyramid, you are narrowing the enterprise choices that are most suitable for your current situation.
Seek the input of others while moving your way up the pyramid. Farmers or other farm service providers who are familiar with enterprises under consideration will be of great help as you figure out what might work for you. Your local Extension Educator is a good resource in knowing what crops are productive and assisting you in calculating crop budgets.
Also, the Small Farms Program offers several online courses for people who are beginning to plan their farm enterprise. Our most basic course, Taking Stock: Evaluating Your Resources and Choosing a Farm Enterprise, uses the material from this tutorial as well as the Getting Started section of this site, but is led by instructors, and offers a more dynamic learning experience with farmer-presenters and opportunities to talk to others who are just getting started in farming.