It's likely that his friends from Konoha would launch a rescue mission. Sasuke might be the first to act out of his sense of rivalry and comradeship with Naruto. Sakura would also be desperate to save him, using her medical skills and combat abilities. And Kakashi could lead the mission, devising a clever plan to infiltrate Iwa and get Naruto back safely.
Well, he could be tortured for information about Konoha. The Iwa ninjas might try to extract secrets about new jutsus or strategic plans. They could also use him as a bargaining chip against Konoha.
Well, one possibility is that Naruto would face a lot of distrust in Iwa at first. He's from Konoha, after all, which has had a history of conflict with Iwa. But Naruto being Naruto, he might gradually win over some of the Iwa ninjas with his determination and unique skills. He could learn new jutsus specific to Iwa's style of fighting, which would make him an even more formidable ninja.
One possibility is that Naruto is being captured for a misunderstanding. Maybe Konoha has received false information about Naruto being a threat. In the fanfiction, this could lead to his friends having to prove his innocence.
Well, one possibility is that Naruto's friends would immediately start a rescue mission. They'd gather all the intel they can about Kumo's defenses and where Naruto is being held. Maybe Sasuke would put aside his differences for the time being and team up with the others.
Well, he might face a lot of challenges. The people in Iwa could be initially hostile as he's from Konoha. He'd have to prove himself. Maybe he'd learn new jutsu unique to Iwa's style.
Well, Naruto might face a lot of challenges in Iwa. He could encounter new types of jutsu that are unique to Iwa ninjas. Maybe he'll make some new friends or foes there.
Well, one way Naruto could defeat Iwa in fanfiction is through strategic alliances. He could team up with other ninja villages or powerful individuals who have a grudge against Iwa. Together, they could plan elaborate attacks and outwit Iwa's military strategies. Also, Naruto's ability to inspire others might lead his allies to fight more bravely, giving them an edge in the battle.
Another way is that he forms an unexpected alliance within Iwa. There could be a dissident group in Iwa who oppose the capture of Naruto. They might help him escape in exchange for some future favor or because they believe in Naruto's cause. Naruto has a way of inspiring people, even those who are initially his enemies, so this is a plausible scenario.
In a 'naruto gets captured' fanfiction, he might be tortured for information. His captors could be after the secrets of his Nine - Tails chakra. They may try to use him as a bargaining chip against Konoha.
Maybe Naruto is captured by a powerful and mysterious foe. This enemy blinds him as a form of torture. Naruto's friends and allies in Konoha soon notice his absence and begin a search. Naruto, while in captivity, tries to figure out the motives of his captors. He also tries to find ways to escape, using his chakra to sense his surroundings despite his blindness.
Well, it could be that Sasuke captures Naruto as part of a plan to protect him from a greater threat that Naruto is unaware of. Maybe Sasuke has some inside information about a powerful enemy who is targeting Naruto, and by 'capturing' him, he can keep Naruto in a safe place until the danger passes.