It would depend on the writer's intention. If the focus is on Naruto's growth, he could start exploring new jutsu or forms of chakra control. Since he was revived by Madara, there might be some dark elements associated with his revival that he has to overcome. Maybe he has to fight off some sort of curse that came with the revival process. And he would have to do this while still trying to protect the people he cares about.
Sasuke would be very cautious. He has a history with Madara and would be on guard. He might not trust Madara even if Naruto believes in him.
The story would likely shift focus to Naruto's actions. He'd probably start by assessing the situation of the war and then use his abilities to start making a difference.
It could start with Naruto being in a new realm of power, and Deathstroke somehow getting involved in his training. Maybe Naruto is seeking new challenges and Deathstroke offers his expertise. Then, they would start with basic combat training, with Deathstroke pushing Naruto to his limits. As the story progresses, they might face common enemies that require both of their skills to defeat. And Naruto would gradually incorporate Deathstroke's teachings into his own fighting style.
Well, it could involve Madara having a new purpose. Maybe he decides to help Naruto against a new, greater threat. Since he was revived, he might have a different perspective on the ninja world now.
Well, it could go in many ways. Maybe Naruto wakes up with a newfound power. He might then start to seek out his friends and allies to tell them he's back. And then they could plan their next move against their enemies together.
In this fanfic, Naruto's character development would be really interesting. Having Madara's power would force him to look at the ninja world from a different perspective. He might start to understand the reasons behind Madara's actions, at least to some extent. This new understanding could make him more empathetic but also more determined to find a better solution for the ninja world. His growth would not only be in terms of power but also in terms of wisdom and leadership. He would need to learn how to control the power without being consumed by it, which would be a major part of his character arc. His interactions with his friends would also be different. Some might be in awe of his new power, while others might be worried. Naruto would have to navigate these relationships while also dealing with his own internal changes.
In a 'kawaki kills naruto' fanfic, the story would likely take a very dark turn. The characters would be forced to reevaluate their relationships and loyalties. Sasuke, for example, would be deeply affected as Naruto was his closest friend. He might be torn between seeking revenge and trying to understand what drove Kawaki to such an act. The new generation of ninja, like Sarada and Mitsuki, would also be involved in the aftermath. They might be caught in the middle of the conflict between Boruto and Kawaki, trying to find a way to restore peace while dealing with their own feelings of loss and confusion.
If Naruto was revived by Edo Tensei in fanfiction, the story's dynamics would shift significantly. For one, his revived self could bring back forgotten techniques or knowledge. This could help in battles against stronger opponents. Also, his return would likely cause emotional turmoil among his friends. Some might be overjoyed, while others could be conflicted about his undead state. And his actions could set off a chain of events that would rewrite the entire plot of the fanfiction.
Naruto would likely be more conflicted. Knowing he's related to Madara, who was a major antagonist, would make him question his own identity. He might be more secretive about this part of his heritage at first.
In a fanfic where Naruto is trained by Madara, Naruto might gain some extremely powerful and unique jutsu. Madara is a very skilled and experienced shinobi. He could teach Naruto some ancient and forbidden techniques that are not known in the regular Naruto world. This could make Naruto an even more formidable opponent, perhaps with a new style of combat that combines his own natural abilities with Madara's dark and powerful knowledge.