Well, he might start by using his charisma. Naruto has always been good at making friends. He could reach out to old allies from his village, like Shikamaru and Choji. Also, he might convince some of the outcast ninja who have been mistreated in other villages to join him. His reputation as a hero who saved the world would surely attract a lot of people.
One challenge is trust. Not everyone will immediately believe in Naruto's intentions. Some may think he is trying to gain power for himself. Another challenge could be resources. Feeding, housing, and training an army requires a lot of resources. He needs to find ways to get enough funds and supplies.
Obviously, his friends Ron and Hermione would be among the first to join. Neville could also be a key member, as he has shown great courage. Then there might be the members of Dumbledore's Army who are still at Hogwarts. The Weasley twins could also be part of it, using their unique magical inventions to give the army an edge in battle.
In this fanfiction, Harry might start by gathering his most loyal friends like Ron and Hermione. They could then recruit other students who feel oppressed by the Death Eaters' regime at Hogwarts. Harry could use his knowledge of magic, especially defensive spells, to train the army. Maybe they'd also include some magical creatures, like the centaurs or the house - elves who are willing to fight for a better future at Hogwarts.
Perhaps Naruto decides to build the kingdom as a refuge for those affected by wars. He'd face challenges like getting resources, dealing with neighboring villages' suspicions. He might use his Uzumaki bloodline powers to create a protective barrier around the kingdom and start a new ninja academy there with his own ideals.
The plot could be that Naruto has a vision of a great threat coming from outer space. So, he decides to build a spaceship. He starts by learning about advanced technology, perhaps from some hidden ninja scrolls that contain knowledge from an ancient civilization. Along the way, he faces challenges like getting the right parts and dealing with those who oppose his idea, thinking it's too dangerous. His friends like Sasuke and Sakura might join him, each contributing their own skills.
I think Rock Lee could be an important ally. His determination and strong work ethic would inspire the people in the kingdom. Hinata would also be there, supporting Naruto with her gentle nature and Byakugan skills, which could be useful for surveillance. And of course, the Nine - Tailed Fox inside Naruto could also be an unexpected ally, providing power when needed.
I think Rock Lee would be there to help. His unwavering dedication would inspire the new villagers. And Hinata, with her kind heart, could help in creating a warm and inclusive community. Maybe even some of the older ninjas like Kakashi could offer their wisdom and experience.
Well, one possibility is that Naruto might use his unique ideas from his travels to create a village that focuses on different ninja arts than the traditional ones. Maybe he'll incorporate new training methods he learned from his friends around the world.
One possible plot could be that Fem Naruto, with her unique skills and charisma, starts by uniting a small group of outcasts. She uses her ninjutsu in new and creative ways to protect them and gain resources. As time goes on, she attracts more and more people, gradually building a small village that evolves into an empire. She might face opposition from traditional ninja villages who see her as a threat.