~And I think poker courses are not really that relevant as people get to know more and develop more skills in poker games if they often play it in casinos. I’m not saying that these courses are useless, but people actually learn more from their own experience.
It can be true of some things, but not about poker. Yes, you could learn a lot from your own experience if you were someone playing 20 tables at ones, 10 hours per day for 20 years, but it would be much easier, and faster, to learn how to play from a pro.
However, if you want to gain more customers, you should have post these courses here and at least give some details about it so that the people here will develop interest in it.
It's actually a good advice. OP is promissing to "explain everything in detail" via PM, but it would be better to see at list some details here in this thread.