Naruto would first be extremely confused by the rules of the Death Note. His understanding of power and its consequences is rooted in his ninja training and his own moral compass. The Death Note's rules, which seem so simple yet so deadly, would be completely foreign to him. He would question why anyone would create such a thing and would be very hesitant to even consider using it, as it goes against everything he stands for in his world of ninjas, friendship, and protecting the innocent.
It focuses on the story of L's early days and how he solves cases. In this novel, we see L's unique detective methods and his battle of wits against various criminals.
Light dies when his name is written in the Death Note by Ryuk. Ryuk, who was the shinigami that gave Light the Death Note, decided to end it as per the rules.