I dropped out of HS at 17, I don't even have a GED. I'm going to get it soon and am debating enrolling in junior college I just don't want to study.
Then consider a trade. I'm not in a union but I think they're common in the US. You could talk to a local branch about trade specific earning potential, training time, etc.
A licensed trade would probably be the way to go. I doubt a licensed union plumber, electrician, refrigeration tech, etc makes less than $80/ hr. Probably stay away from non-licensed trades like tiling, drywall, carpet/vinyl/flooring, etc. Carpentry is a maybe, and would give you the easiest transition into business ownership as a builder/GC later on.
There are also non-construction trades here, such as butcher, baker, hairdresser, etc.