You'd have to give us the context, but in general they are not interchangeable. In fact, it's not easy to come up with an example where they are both grammatically possible, and in such cases, they would have different meanings. Perhaps in something like "I don't know how any/many of you passed your exams". In the first one "how" means "in what way", and in the second, it works with "many" to mean "the number".

"How any" is wrong, where have you seen that?