Well, he could start a family with Hinata and have lots of kids, passing on his Uzumaki bloodline. Then, he could encourage his friends who have some Uzumaki connection, like Karin, to also have families and pass on their Uzumaki genes. He could also set up a school or training center in the Uzumaki land, teaching the Uzumaki ways of life and ninjutsu, which would attract orphans or those who want to be part of the Uzumaki clan.
Gaara could be an important ally. He has always been Naruto's friend and as the Kazekage, he could provide resources and support for Naruto's plan to revive the Uzumaki clan. Maybe he could offer building materials to help rebuild Uzumaki settlements or send some of his shinobi to help with security during the revival process. Another possible ally is Tsunade. She is a Sannin and has a lot of knowledge and influence. She could help with medical research related to the Uzumaki clan, like finding ways to preserve their unique genetic traits or heal any potential genetic diseases within the clan. Also, she could use her political influence to get other villages to support Naruto's plan.
The ninja world would be in shock. Mito Uzumaki was a very important figure in the past. Her revival could bring a lot of ancient knowledge back. For example, she might know some secrets about sealing jutsu that have been lost over time. This could change the balance of power among the villages.
It could be that Naruto finds a way to reverse time in a small area. This would require an extremely powerful and dangerous technique. He might have to sacrifice something in return, like some of his own memories or a part of his chakra permanently. But if he manages to do it, he could go back to the time when Mito Uzumaki was still alive and bring her forward to the present.
Naruto could learn about the Uzumaki clan's sealing techniques. They were masters of sealing jutsu. In the fanfiction, he might find out how they developed these complex and powerful sealing techniques, which were passed down through generations. It could be that he discovers some unique seals that were only known to the Uzumaki clan and how they were used for various purposes, like containing powerful entities or storing chakra.
Naruto could also offer incentives for Uzumaki to have children. For example, providing better living conditions, education, and protection. He might also use his influence to find suitable partners for the remaining Uzumaki members, both within the village and from other allied villages. This way, they can start new Uzumaki families and gradually increase the clan's numbers.
Well, in some fanfictions, Naruto might start by finding suitable partners within the village. Since he is the last of his clan, he could look for women who are willing to carry on the Uzumaki bloodline. He may also use his influence as a hero to encourage others to support his clan - revival efforts, like getting the village to provide resources for the new Uzumaki generation.
There are fanfics that center around the Uzumaki clan's origin. Some might describe how they came to be so powerful in sealing. A really good one could be a story where the Uzumaki clan members who survived the destruction of their village, other than Naruto's mother, come back and help Naruto understand his heritage better. They could teach him things that even Jiraiya didn't know about the Uzumaki.
The Uzumaki clan bloodline can also be used in fanfics to explore family and heritage. Characters might discover long - lost secrets about their Uzumaki ancestry that change their view of themselves and their place in the ninja world. It could be something as simple as a new jutsu that was forgotten by the clan but is now accessible to the main character because of their Uzumaki blood, or it could be a much deeper connection to a prophecy or an ancient power.