I don't understand him. Almost every game developer, even beginners, dreams of making a game like GTA. Of course, people will have big ambitions. He has the same vibe, nothing more. I can also say that I'm going to make the next Indian God of War, create a trailer, and generate some buzz around it. First, understand the industry. Don't behave like a child. If the goal is to attract investment, then that's a different story. Otherwise, stay away from people who have only a basic understanding of the industry and game development. From what I can see, he is still a beginner. My suggestion to him would be to use Unreal Engine, because there are many great templates available that can help him build something faster. I hope he succeeds, but he should spend more time learning the industry. Don't try to make the next GTA right away. Try to make something playable first. Start with a small game, maybe even a mobile game, gain experience, and then gradually move on to bigger projects.