All juvenile charges are considered delinquency. They can all result in detention, curfew, community service, drug testing, drug treatment/drug court, probation, fines, costs and loss of license. Technically, it is a minor misdemeanor though, assuming it was marijuana paraph.
If your conviction is expunged/sealed (that's a big IF), a potential employer will most likely not be able to see your conviction. There are exceptions for certain professionals (teachers, lawyers, doctors), where the Bar or Boards can see those charges. Prosecutors, law enforcement and courts will still be able to see them.
As to your final question, it depends on how the question was asked. Many times it asks the question and says "regardless of whether expunged/sealed."