One of the most shocking revelations could be Naruto's early days as an outcast. Boruto, who has always known his father as a respected figure, would be surprised to learn that Naruto was once shunned by the village. Another could be the danger Naruto faced as a young ninja, like fighting against the Akatsuki. It's so different from Boruto's relatively more sheltered life in the beginning.
The revelation about Naruto's training and how hard he had to work to gain power would be quite startling for Boruto. He might have thought Naruto was just naturally strong. But finding out through fanfiction that Naruto had to endure grueling training sessions, often alone, and with little support in the beginning, would make Boruto realize that his father's success was not just handed to him. This could change Boruto's perspective on his own training and growth.
Another aspect could be Naruto's training with Jiraiya. Boruto might read in the fanfiction about how Naruto traveled with Jiraiya, trained hard, and grew not just in strength but also in character. Jiraiya taught Naruto many important lessons about life and being a shinobi. This could give Boruto a newfound respect for his father's journey to becoming the Hokage.
If Boruto finds out about Naruto's past through fanfiction, it could initially create a sense of awe. Boruto might start to understand the hardships his father faced more deeply. He could become more empathetic towards Naruto. For example, learning about Naruto's lonely childhood might make Boruto appreciate his father's presence in his own life more. This discovery could also inspire Boruto to be more like his father in terms of determination and never giving up.
Well, Boruto could be very inspired. Naruto's past is full of struggles, from not having parents around to being constantly underestimated. When Boruto discovers this in the fanfiction, he might realize that his own problems are not as big as he thought. He could be motivated to work harder and not take for granted the things he has, seeing how much Naruto had to fight for everything.
Boruto might be in awe. He has always known his father as the Hokage, a powerful and respected figure. Seeing Naruto's past full of struggles, loneliness, and determination would make him realize how far his father has come. It could also make Boruto more empathetic towards Naruto and perhaps inspire him to be more like his father in some ways.
One key event could be Naruto's time at the Ninja Academy. He was often alone and had no one to practice with, yet he still persevered. Boruto would see how Naruto's determination started early. Another event might be when Naruto fought against Haku and Zabuza. It was a dangerous battle that showed Naruto's courage. And of course, Naruto's training with Jiraiya would be important. Jiraiya taught Naruto so much, and Boruto would understand how this mentorship shaped Naruto into the person he became.
Maybe it's the high expectations that Naruto has for Boruto. Naruto is a hero, and he might unknowingly put a lot of pressure on Boruto to follow in his footsteps. Boruto could be scared of not being able to meet those expectations.
His presence could create a butterfly effect. Small actions he takes might change the future. For example, if he teaches a young ninja a new technique, it could change how battles are fought in the future.
Obviously, Naruto himself is a crucial character. His experiences and growth form the backbone of the story.
Sasuke is very likely to be involved. He has a close relationship with Naruto and is also an important figure in Boruto's life. His skills and knowledge could be crucial in any adventure or situation that Naruto and Boruto find themselves in. Another character could be Hinata. As Naruto's wife, she would surely be concerned about any strange events involving Naruto. And for Boruto, she is his mother, so she would play a role in any family - related or village - threatening situations.
One interesting plotline could be exploring Naruto's early days of training with Jiraiya in more detail. Maybe showing his struggles and how he overcame them during that time.