In three hours what was learned was to be extremely dangerous in traffic, not how to drive. This is also true of any 16 or 17 year old with 20 hours of driving instruction.
Mastering the correct connections between situational awareness, unconscious motor responses to the various stimuli required to be a safe driver will take a significant number of hours behind the wheel, and you shouldn't endanger anyone else while you acquire that mastery.
Hopefully this was a long time ago and you have accumulated the hundreds of hours behind the wheel without incident. But you did not 'learn to drive' in three hours, you learned to operate a vehicle. The learning to drive part happened after that.