What should one do who unintentionally scraped another car and left the scene based on a companion's advice, then regretted their action, fears that the owner of the damaged car will not forgive them, and is afraid of the supplication of the wronged?

If the driver's vehicle scrapes another car and causes damage to it, he is obligated to repair the damage or pay compensation for it, even if the damage is minor. It was his duty to leave a means of contact for the car's owner. If he is unable to reach the car's owner, he may give charity on his behalf with an amount he believes will absolve his responsibility.