Does he have a college scholarship? If so, he should take it, and take some engineering classes. It's a way to find out if he likes it, at least to some degree. But he should also take some other classes - science and humanities, to find out what else he likes.

If he doesn't have a scholarship, same thing, but at a community college.

But the people telling him he'd be good at it see something. "I'd be good at it" is not the same as "I'd like it", but we often enjoy things we're good at more than things we're bad at. (Also, it's often easier to get jobs in things we're good at.)