I understand you feel like you're stealing history by writing this. But what you write is just fanfiction, i.e. you just use the author's characters and world, but you don't make money from it. Many people like to read such stories to relax and some people write such stories to disconnect from everyday life. Many authors of books sometimes read different fanfictions to stimulate their imagination. So in my opinion everything is fine as long as you don't make money from it, because when you make money from fanfictions we can talk about stealin. So please continue the story of Naruto Namikaze.