Every boy needs to have plan to make a positive contribution regardless of what his goals are. If he sees himself as the modern equivalent of the tribe of Levi and sees that he has a future as a teacher of Torah, he needs to start planning for that role. He has to see that he has the talents needed to become an effective teacher, and then be willing to develop those talents. He has to get honest feedback about his potential as a teacher. If the feedback is that teaching is not for him, then he has to find another area to make a contribution.
Sitting in learning as long as possible and expecting to be supported by a rich father in law is not a plan.