You want to be an upright citizen with opportunities for a good career, however you have a criminal record which you feel will bar you from advancement in life. In State courts you can often seal a State record after a certain length of time and depending on the crime. An attorney can aid you through the procedure.
However, if your crime happened to be a federal offense, be prepared to spend enormous amounts of money just at the chance to seal your record. The odds are against you because the federal courts have ruled that only in rare situations will the court seal a record-and I mean rare.
Your crime could have been minor, it does not matter. A less expensive and perhaps even better gamble would be to write a personal letter to the President of the United States asking for a presidential pardon.
Sorry folks. Once you are branded by the federal system it is likely a lifetime stain. It reminds me of the novel Les Miserable in which the hero was thrown into prison for many years for stealing a loaf of bread to feed his family. Once he served his time, no one wanted to help an ex-convict and the police were always suspicious of him. He eventually changed his identity in order to get some semblance of a good life. However, even then he eventually ended up dying at the hands of an overzealous cop.
My advice to you is to fight any federal charges from the beginning and not to plead guilty, unless you truly believe that the deal offered by the US Attorney's office is good and your chance of a conviction and severe punishment is high.
If you find yourself in the unenviable position of having a federal criminal record, all I can suggest would be to do your best to explain the circumstances in a light favorable to you when a nosy employer asks. Write a summary of the incident explaining it from your point of view and attach it to your job application. If it is well written, it may even improve your chances of getting the job.
As our government churns out more and more criminals with its arbitrary enforcement of arbitrary laws, more and more employers will become more and more understanding of your plight. Good luck.