Target group and my modules

I’m in the process of putting together a program to coach on whole food plant based (WFPB) diet and lifestyle.

My first question is do I need to narrow it down to who the target is or can I just leave it to whoever needs and want to go WFPB diet and lifestyle? If I need to narrow it down, one group that comes in mind is the people who have had some sort of health issue, for example, heart problems and were told that WFPB diet will help them but they don’t know where to start. Another option would be to target all people with some sort of health issue and not specifically hearth and cardiovascular.

My second question is: I’m almost certain that I will apply to become a life coach at your school. Do you think I should start developing my WFPB programs (the 6 modules/programs Brook describes) before I go through my certification or should I wait to do my program after? I have zero experience in marketing and selling anything!