What should I buy or plan for my boyfriend who just turned 19 and is a Capricorn?

What sort of things is he interested in like hobbies or maybe what he already does or would like to do for a career? Does he have his own car? If he does, maybe there is something that he might like for his car.

You can send him birthday flowers card along with a gift like any electronic gadgets or any book or any sports item according to his field of interests.