Well, in fanfiction, one way could be that some Kumo ninjas are given the Sharingan as a gift or a curse from an ancient being. They then start to form a special group within the village dedicated to understanding and mastering the Sharingan. This group would share their knowledge with others, and over time, the Sharingan becomes an important part of Kumo's ninja heritage, with its own set of training methods and traditions.
One interesting storyline could be a character from Kumo who obtains the Sharingan through some mysterious means. Maybe they were part of a secret experiment that combined the powers of different ninja villages. This character then has to struggle with the new power, as it comes with a price, like a constant battle against the dark urges that the Sharingan can bring. They might also face discrimination from their own village who fear their new, unknown power.
Naruto would probably use his friendly and outgoing nature to adapt. He'd start by getting to know the people around him, like his new family and the local ninjas. He might also be interested in Kumo's unique jutsu and training methods, which would help him fit in. And of course, he'd keep his goal of promoting peace between Konoha and Kumo in mind, which would give him the motivation to overcome any difficulties in adapting.
Yes, in fanfiction, anything can be possible. Writers can create alternate universes where Naruto is born in Kumo instead of Konoha. They can come up with various reasons for this change, like a mission that led his parents to Kumo before his birth or some sort of political arrangement.
Maybe he's running away from some kind of danger or threat in his home village. There could be a group or an individual after him, and he believes that Kumo would be a safer place. It could also be related to some political unrest in Konoha that makes him feel like he has to leave, and Kumo seems like a viable option.
It could be Killer Bee. He's a very well - known and powerful ninja from Kumo. His unique fighting style and his status as a Jinchuriki would make him a great candidate to be the one who saves Naruto.
Adapting to a new ninja system could be a big challenge. Kumo may have different training methods, rules, and traditions compared to his home village. Naruto would need to learn and adjust quickly if he wants to survive there.
He could meet some rogue ninjas. These ninjas might either try to harm him or, in some cases, offer to help him on his journey. They might have their own reasons for being in the area between Konoha and Kumo.
He could meet the Raikage. The Raikage might be initially skeptical of Naruto but could later see his potential. There are also other strong ninjas in Kumo like Killer Bee. Naruto might cross paths with him and they could have some interesting interactions, perhaps even training together.
Naruto would probably be defiant. He's not the type to just sit there and be a victim. He'd likely be shouting at his captors, telling them they made a big mistake.