You this young man, he's a success, he's an important man, philanthropist, he's proud of his roots and where he comes from. He's donating money to his school in his South London home town, jet setting, all of accolades and triumphs of his hard work. Then you see the real him, a townie, never graduated college, single, and life on the verge of collapse, he still has all the same passions, but he's not living the dream, and that success version was just harmless dreaming and wishful thinking. Maybe writing this from a point where fantasy self cuts back/snaps back to reality self. Since I'm the writer and I'm boss and I can have anything I want, let's say this guy one day gets to live the dream, like, as the story unfolds, and, it turns out it's nothing how he thought it'll be.
I know this is probably nowhere near to your initial vision, but that premise screams simulation to me. Maybe the character gets lucky and earns enough money to go to a simulation bar, wherein his dreams are programmed into his own personal experience. It's great the first few times but then everything starts to go south as this ideal world of his falls apart on him, because the choices he makes in the simulation are just as damaging as the ones he's made in real life, the ones that see his life on the verge of collapse. Perhaps out of desperation he steals money to go back into the simulation, obsessed with trying to fix his 'life', without realising he's ruining his own life in the real world all over again, wasting the money he's earned/stolen that could get him back on track. Eventually the simulation and the real world bleed into one and he can't the difference any more. Just a thought based on your last sentance 'it turns out it's nothing how he thought it'll be'. I think sci-fi would absolutely be the best fit for this kind of story. Hope this helps friend, happy writing!
The worst thing to find out at the end of a story is that it was all a dream. If you have the dream of the perfect be a preface and then show him working up to being that over the course of the story that'd work out great.
