Sorry if it's too long, but it's worth reading. Describing a person as ''חם'' would not be correct, as you use ''חם'' for things that are literally hot, e.g This plate is hot - ''הצלחת הזאת חמה''. The sentence you mentioned would be used if you'd feel a hot skin when you touch it... But as people described in other comments, ''לוהט'' practically means the same but also not often used. Its literal is something hotter than hot, like it burns or something - ''האש לוהטת'' The fire is very hot. ''חתיך'' and ''יפה''are the most likely to be used in a conversation. Hope I helped :)
I disagree somewhat.
In Hebrew, אדם or בין אדם is used for person or human without regard to gender.
I would say that the distinction between איש and גבר is that גבר is used for situations where gender is the point, that is to say, a man rather than someone of a different gender, and איש is used to refer to a man where
I agree with BezalelP that if you're teaching gender specifically e.g. "man" or "woman", it makes sense to use גבר instead of איש.