He could marry Hinata. Even though he's banished, Hinata might follow him because of her deep love for him. Their relationship could develop further outside the village, and they could get married and start a family.
Naruto could marry a character from another village entirely. For example, a strong female ninja from the Sand Village. Since he's banished from Konoha, he might find acceptance and love in a different place, and this Sand Village ninja could see his worth and fall in love with him, leading to marriage.
He could marry Mikasa from Attack on Titan. Just think about it. Naruto's positive and determined personality would contrast with Mikasa's more stoic and protective nature. They could meet through some sort of interdimensional accident. Naruto would be fascinated by the Titans and the world outside his own, and Mikasa might be intrigued by Naruto's ninja abilities.
He could marry Hinata. They have a pre - existing relationship in the original series. Hinata has always had feelings for Naruto, so it would be a natural choice. In the fanfiction, their relationship could progress more quickly, leading to an early marriage.
Maybe he marries an OC (original character). The author of the fanfic could create a whole new character with unique qualities that attract Naruto during his time away from Konoha.
Another possibility is that Naruto marries a completely new character. This character could be from a far - off land that Naruto visits during his departure from Konoha. She could be a powerful ninja in her own right, with unique abilities and a personality that attracts Naruto, leading to their marriage.
He would surely meet Gaara. Gaara, having had his own experiences of being an outcast, would likely be one of the first to interact with Naruto. They could share their stories and become good friends.
Well, if Naruto is banished and gets married in a fanfiction, it could go in many directions. Maybe he marries a foreign ninja. His banishment could be the start of a journey where he discovers new jutsu and cultures. His marriage could be a political alliance as well. His new wife could be from a powerful clan in another country, and together they could work towards peace between their lands while also building a loving family.
Hinata could also be a common character. She may try to help Naruto secretly, or be heartbroken by his banishment and strive to change the village's decision. Another character could be Kakashi. He might be one of the few who believe in Naruto's innocence and try to find a way to bring him back to the village.
Danzo could be a great antagonist. He might see Naruto's new married status as a threat to his power - he could spread false rumors that lead to Naruto's banishment. He would then try to eliminate Naruto and his wife to ensure his own control over the village remains unchallenged.
It could be a hidden group within Konoha that was behind Naruto's banishment. They might be afraid of his growing power and influence. This group could work in the shadows to stop Naruto from ever returning to Konoha and regaining his status.
Maybe some local tribespeople who have unique abilities or knowledge. For example, they could teach Naruto some ancient techniques or survival skills that are not known in the Hidden Leaf Village. There might also be wandering samurai or other shinobi from different regions who pass by the outpost and interact with Naruto.