You do not need to union to registered as an apprentice. There are other apprenticeship schools other then the union. I know in Maryland,on prevailing wage projects, you can classify a person as a laborer, but they are restricted as to what job functions they can perform. NO hand tool use, No ladders. Brooms and shovels, move materials -OK You need to check into your local state as to what the rules are . There should be person who comes to the project to verify people etc They will answer ALL your questions. Ask them !
In this life time the only person you can count on to look out for you is ..... YOU !