It will depend on the specific felony. Unlawful sexual contact with a minor has no statute of limitations. Other crimes will vary.
for the rest of your life
If you were charged after you became an adult the charge becomes a permanent part of your criminal history record.
Felony Charges Stay in your Specific State Permanently. They will also stay in your background for good too no matter if the Felony has been set aside from a Suspended Sentence or not. If you qualify...
The record of your arrest and conviction will always exist. Your criminal history does not "go away" after any period of time.