Well, it would be a whole new level of difficult. Naruto is known for his energy and his ability to adapt quickly. But being deaf and blind, his adaptability would be tested to the extreme. He wouldn't be able to use the Rasengan in the same way, as it requires visual focus on the spinning chakra. Also, communication would be a huge problem. He couldn't communicate with his team as effectively. He might have to learn some form of sign language through touch or develop a unique way of sensing the thoughts of others. His relationships with characters like Sasuke and Sakura would also change drastically as he couldn't interact with them in the normal ways.
It would change his journey completely. First, his perception of the world around him would be very different. He'd have to re - learn everything. In the Hidden Leaf Village, he'd face a lot of discrimination probably, as some might see him as a liability. His combat style would likely shift to a more defensive one, relying on his sense of smell to detect enemies and his sense of touch to counter attacks. Training with Jiraiya would be almost impossible in the traditional sense. Jiraiya couldn't teach him new jutsu in the normal visual and auditory way. Naruto would have to find a new way to connect with his inner chakra and use it without relying on his sight and hearing, which would be a long and arduous process.
One potential ally could be Hinata. Hinata has a very gentle and empathetic nature. She could help Naruto by using her Byakugan to be his 'eyes' and describe the world around him. For example, in battle, she could tell him where the enemies are. Another could be Kakashi. Kakashi is a very experienced ninja. He could develop special training methods for Naruto that are more focused on his remaining senses. He could also use his Sharingan to sense threats and communicate that to Naruto in some way, like through a series of taps or vibrations.
Naruto's growth would be affected in several ways. Anko could teach him different combat techniques. Since she's skilled in close - range combat and stealth, Naruto might become more proficient in those areas. He could also learn more about the psychological aspects of being a ninja from her. Anko has her own demons from her past with Orochimaru, and she could pass on her knowledge of how to deal with the mental pressures of the ninja life to Naruto.
First, research about blindness and deafness. Understand how people with these conditions experience the world. For the Naruto part, study the ninja techniques and the world - building of Naruto. Then, create a character with these disabilities. Maybe they have a special ability that compensates for it, like a super - sensitive touch that can detect chakra. Outline a story where they face challenges in the ninja world but also find acceptance and friendship.
His ninja skills might be completely different. He could have alien - like abilities added to his ninja moves. For example, he might be able to use some kind of energy projection that is common among the aliens who raised him instead of just chakra - based jutsus. He could also have a different understanding of combat strategy, influenced by the alien culture's way of fighting.
He has trouble moving around. Without sight, he can't easily navigate the village or the forest. He might constantly bump into things. Also, in combat, he can't see his opponents' attacks coming. It's a huge disadvantage compared to when he could see.
Naruto's blindness would surely transform his relationships. His friends would need to adapt. Shikamaru, being the intelligent one, might come up with strategies to help Naruto move around safely. Choji could share his food more often to cheer Naruto up. Ino might use her mind - transfer jutsu in new ways to assist Naruto. His friends would become his eyes in a way, and this new dynamic would deepen their friendships as they all work together to support Naruto in his new situation.
He could also become more cautious. If his dad is into Aizen's ways, Naruto might be more aware of the potential for deception and hidden motives in others. This could make him a more astute ninja, but also a bit more paranoid. For example, he might be more hesitant to trust new allies right away.
In the fanfiction, Naruto might overcome his blindness through his extraordinary sense of hearing. He could learn to detect the slightest movements and sounds, using it to his advantage in combat. For example, he could sense the wind direction changes when an opponent attacks, and dodge accordingly.
His relationships would be completely turned upside down. For example, Naruto wouldn't have the same camaraderie with his fellow Leaf Ninja. Instead, he would form new bonds with the Sound Ninja. He might have a mentor - like relationship with Orochimaru or one of the other high - ranking Sound Ninja. His relationship with the villagers of Konoha, who once shunned him but later accepted him, would be one of hostility. And his relationships within the Sound Ninja village would be based on their own values and power dynamics.
His training might become easier in some ways. For example, if angels have natural agility, Naruto could pick up new ninja moves more quickly. He might also have an inborn sense of balance that helps him in acrobatic ninja stunts.