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.
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.
Well, in this 'Boruto goes to the past fanfiction', Boruto could potentially change some events in the past. Maybe he tries to prevent some of the tragedies that his father and the others had to endure. But he would have to be very careful because any small change could have big consequences for the future. He might also learn some long - lost ninja techniques that were forgotten in his time, and bring them back to the future to make Konoha even stronger.
Well, often in these fanfictions, Boruto watching the past can lead to him learning about the great battles that his predecessors fought. He may witness the Fourth Great Ninja War and see the heroic deeds of his father and the other ninja. This could either make him feel pressured to live up to their legacies or give him the motivation to carve out his own path in the ninja world, different from what has been done before.
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.
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.