If you are charged with a federal drug crime, then you may be eligible for the benefits of 18 USC 3607. That statute allows the judge to defer entering the judgment of guilt and place you on probation for no more than one year. If you succeed, then the judge can dismiss the case and you would not have a conviction on your record.
As a further benefit, if you were under 21, you could then apply to the court to have your record expunged. If you were 21 or older, and you did not take advantage of the deferred sentencing, you may have to look at other options such as a presidential pardon.