Not automatically, but the odds are stacked in a way that most people outside the system do not fully appreciate until they are inside it.
Federal prosecution is not like what you see at the state level. The resources are different, the preparation is different, and the conviction rate reflects both. Federal prosecutors win roughly 97 percent of the cases they bring to trial. That number exists because federal agencies, whether the FBI, DEA, ATF, or any of the others, spend months or years building a case before an arrest is ever made. By the time charges are filed, the government typically has recordings, financial records, cooperating witnesses, and a file thick enough to make a jury lean before opening arguments are finished.
That does not mean prison is inevitable. Cases do get dismissed. Plea agreements can result in probation for lower-level offenses. Cooperation with prosecutors can reduce both charges and sentencing recommendations significantly. First-time offenders with limited involvement sometimes avoid incarceration entirely depending on the nature of the offense and the sentencing guidelines that apply.
But here is the reality: federal court is not a fair fight in the conventional sense. The government chooses when to move, controls the evidence timeline, and has no budget constraint on building its case. A private defense attorney, however good, is working against that from day one.
The single most important thing your person can do right now is retain an experienced federal defense attorney, not a general practice lawyer, but someone who works federal cases specifically. The decisions made in the earliest stages, before arraignment, before discovery, often determine how the rest of the case unfolds.