I am astonished, almost to the point of being amazed. Let me explain.
After you past the insurance test and get licensed in the state you past the test, that is the end.
Everything is radio silence, UNLESS you were doing this to work as a captive agent.
A captive agent means that you work FOR an insurance company...like Allstate. A JOB.
If you are doing this to be "uncaptive" or a "broker" to represent several insurance companies then nothing, you are totally on your own to figure it out.
As I was studying for my license the topic/type of insurance that interested me the most was for eldery - Medicare. I also certainly have an interest in Cancer Insurance (I know the importance of it) and Life Insurance, but when I looked at where to start it seemed to me that everyone turning 65 will need Medicare so you have people who actually need the insurance.