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.
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.
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.
It could strengthen their bond. As Boruto learns about Naruto's past achievements and the challenges he overcame, he might feel proud to be his son. He may start to see Naruto not just as his father but also as a hero, which would bring them closer together. Boruto might be inspired to follow in Naruto's footsteps more wholeheartedly.
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.
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.
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.
Naruto might feel a sense of responsibility. He would see it as his duty to help Boruto understand and control the Jougan. So, he could start to create special training regimens for Boruto. These regimens would be designed not only to strengthen Boruto's physical and ninja skills but also to help him master the unique powers that come with the Jougan. He would also teach Boruto about the importance of using such power for good and protecting the Hidden Leaf.
Boruto could have visions or dreams that show him Naruto's past. Maybe he enters a forbidden realm or unlocks a secret power that allows him to experience his dad's history.
Obviously, Naruto himself is a crucial character. His experiences and growth form the backbone of the story.
He may try to understand Boruto's reasons. Naruto has always been one to look for the good in people. So, even when hurt, he might give Boruto the chance to explain himself. He could say something like 'Boruto, I know you didn't mean it. Let's talk about what's wrong.' He'll be patient and try to resolve the issue rather than getting angry right away.