Naruto would be devastated. He might blame himself for not being able to protect his son. Sasuke would be angry and would likely go on a hunt for the perpetrator. His friends like Sarada and Mitsuki would be heartbroken. Sarada might vow to become stronger to prevent such a tragedy from happening again.
In a fanfic, it could really depend on the story's direction. If the story focuses on Boruto's growth and he unlocks the full potential of the Jougan, he could be the most powerful. The Jougan seems to have some mysterious and potentially very strong abilities. But Sarada could also become extremely powerful if she manages to awaken new levels of the Sharingan. Naruto, while powerful, may be surpassed by the younger generation in a story that emphasizes their rapid development.
Well, as of now, it's hard to say exactly how long the Boruto manga will be. It all depends on the author's plans and the story's development. But it's been building up a significant amount of content over time.
Boruto's strength in the manga is considerable. He's developed new jutsus and strategies, and has overcome many tough challenges. His potential keeps increasing as the story progresses.
In the manga, Boruto starts off as a pre-teen, approximately 12 years old. As the story progresses, his age gradually increases. But for the initial part, he's 12.
The number of Boruto manga varies over time. Currently, there are several volumes available, but you can check the latest updates on official manga platforms or comic stores for the most accurate count.
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.