The wildlings might be his allies. After all, Jon Snow has had interactions with them before. They are fierce fighters and could fight alongside him against a common enemy.
In this fanfiction, one of the key battles Jon Snow might participate in could be the Battle of the Whispering Wood. His skills as a fighter would be put to good use there, sneaking around and taking out enemies. Another could be a fictional battle near the Wall, where he defends against some new threat that has emerged during Robb's war.
In this fanfiction, Jon Snow's character could develop in several ways. Firstly, his relationships with other characters might change. He may form stronger bonds with his fellow soldiers, learning to trust them more. Secondly, his understanding of politics and power could grow. As he is involved in Robb's war, he witnesses the political maneuverings that go on behind the scenes. This could make him more cynical or more determined to fight for justice, depending on how he interprets these events. Moreover, his combat skills are likely to improve, and this newfound strength could give him a different perspective on his own capabilities and his place in the world.
Well, it could be about Jon Snow leading his men into a great battle against the White Walkers. Maybe he discovers new strategies or forms unexpected alliances during the war.
Jon Snow could potentially have allies like the Mormonts. They have always been loyal to the Starks. Maybe even some of the Dornish houses might side with him. They have their own reasons to oppose the current power structure in Westeros. And of course, his friends from the Night's Watch who left with him or believe in his cause could be his allies in this conquest. He might also gain the support of some of the maesters who see the value in his leadership for the future of Westeros.
He might go back to Winterfell and claim his rightful place as a Stark. This would change the whole power dynamic in the North and also his relationship with his siblings.
A great deal of Jon Snow and Iron Throne fanfictions focus on his relationships. For example, his relationship with Daenerys could be very different in fanfictions. In some, they rule together on the Iron Throne, combining their claims and powers. In others, they are at odds, with their relationship being a major obstacle in Jon's path to the throne. And of course, there are fanfictions where his Stark family ties also influence his actions regarding the Iron Throne, as loyalty to his family is a strong part of his character.
One idea could be a crossover where Jon Snow is transported to the Naruto universe. He could join Naruto's team and use his combat skills from Westeros, like sword fighting and archery, in the ninja battles. His leadership skills might also be recognized in the Hidden Leaf Village.
One idea could be a story where Robert Baratheon discovers Jon Snow's true parentage earlier. This could lead to a complex relationship where he sees Jon as a potential heir or a powerful ally. He might take Jon under his wing, train him in the ways of leadership and warfare, much like he did with Ned Stark's other children.
Fanfiction about Jon Snow and the white dragon can go in many directions. Some stories might explore the origin of the white dragon and how it came to cross paths with Jon. It could be that the dragon was hidden away for centuries and Jon's arrival in a certain place awakens it. The relationship between them could also be one of mutual respect and understanding, with the dragon seeing something special in Jon that makes it want to follow him, like a kind of destiny or prophecy at work.