Boruto's reaction would be complex. He'd be heartbroken, for sure. He might start to question his own worth and purpose. But over time, he'd realize that he has to carry on Naruto's legacy. He'd become more serious and focused. He'd also become more empathetic towards others, understanding the weight of sacrifice. He might even start to study Naruto's techniques and leadership style more closely, trying to emulate the things that made Naruto such a great Hokage and hero.
Well, Naruto would be in a really tough spot. He loves his family and the village, and this situation would be a huge blow to his traditional values. He might struggle to understand how this happened between his son and Hinata. Hinata's family, on the other hand, would be protective of her. Her father would want to ensure that Boruto is taking responsibility. Boruto's friends would also be surprised. Some might be supportive, like Shikadai, who would try to see the good in the situation, while others might distance themselves at first, not sure how to handle this new and rather strange development.
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.
Naruto would likely be excited. He loves his son so much that seeing different stories about Boruto would be like seeing different potential futures for him. He might even get some inspiration from the fanfiction to give Boruto some advice in real life.
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.
The villagers would likely be in shock. Naruto is a beloved figure, but killing his own son would be a very controversial act. Some might turn against Naruto, believing he has gone too far. Others might understand his reasons if they knew the full story, but still struggle with the morality of it.
The ninja world would likely be filled with a mix of reactions. Some would see it as a positive sign of unity between different clans. Others might be worried about the power the baby could potentially have. There could be those who would try to use the baby for their own political or power - hungry motives.