Man inherits unknown fathers billions
Sounds like "Too Much Love" by Tom Frost (the story formerly known as "The Billionaire Life")
Nick Coyle grew up not knowing about the billion-dollar legacy waiting for him on his eighteenth birthday. Money isn't Nick's only legacy, though. A dark history of excess and tragedy hang over both sides of his family. With the world suddenly offering him too much of everything and only five close friends to guide him, will Nick survive?