At 17 and he doesn't know what he wants to do. That seems pretty typical these days.
The trouble is, is that he has had an easy life. He's probably been spoilt and been given every thing he wanted. That is no critisism (my kids are the same) but he doesn't realise what things cost and what it takes to get the things he has.
Your best option is to sit down with him and work out a few figures. Point out that if he wants a place of his own (to bring all these girlies back to) its going to cost X to rent or buy. He will want a car soon. That will cost Y.
Then work out how much he will have to earn in order to get these things. Once you have done that you can look in the job paper and see what companies and what jobs are paying. That may give him an idea of what to aim for. You can't tell him what to do, but with some careful guidance he will probably come to a decission himself