One common scenario is Naruto training with a new or unexpected mentor. For example, he might train with a powerful and reclusive shinobi from a far - off village who has unique techniques to teach. Another is training in a special environment like a pocket dimension filled with dangerous beasts that force him to quickly level up his skills. Sometimes he'll train in a team with other characters who also have something new to offer, like a combination of taijutsu and ninjutsu training that he hasn't experienced before.
Training in fanfictions often makes Naruto more confident. As he masters new skills, he becomes surer of himself in battles and in his interactions with others. For example, if he learns a powerful new jutsu, he'll carry himself with more pride and authority.
One idea could be that Naruto catches a cold because he overexerted himself during the training trip and didn't take proper care afterwards. Maybe he pushed his body too hard with new jutsu training. His friends, like Sakura, could then take care of him, bringing him hot soup and medicine. It would be a sweet moment showing their friendship.
One possible plot could be that Naruto is sent to a secret training ground by an old sage. There, he learns unique jutsu that no one in the Leaf Village has ever seen. He might train in extreme conditions, like fighting against illusions that mimic the strongest enemies. This new training gives him an edge over his peers and he returns to the village a much more powerful ninja.
It could be Kakashi. He has a lot of knowledge and skills that he could pass on to Naruto more intensively. Maybe he takes Naruto on a long - term mission where they train on the go. Kakashi could focus on improving Naruto's Sharingan - like observational skills and help him develop new strategies for combat.
In this fanfiction, Naruto's serious training could be a turning point for his character. As he trains, he might encounter new challenges and mentors that shape his values. He could develop a stronger sense of purpose, not just to be recognized, but to truly master his skills for the sake of protecting his village and friends. This new - found determination might lead him to explore different jutsu and strategies, further evolving his combat style and overall character.
In the fanfiction, Naruto could also learn some spiritual or chakra - based techniques. He might discover a way to use his chakra to sense the emotions or intentions of his opponents. This would give him an edge in battles, as he could anticipate their moves better. Or he could learn a technique that allows him to transfer his chakra to others in a more efficient and powerful way, enabling him to heal or boost his comrades' abilities during combat.
In this fanfiction, Hokage Naruto might take Naruto to a special training ground. There, he could teach Naruto some of his own unique jutsu combinations. For example, he could show Naruto how to combine the Rasengan with his Sage Mode more effectively. This would give Naruto a huge power boost and also make him more confident in battles against tougher opponents.
Perhaps he's been influenced by someone who gives him bad advice. For example, if someone tells him that natural talent is enough and training is overrated. Also, he could be dealing with some personal problems, like a conflict within his family or among his friends that takes up all his time and mental energy, causing him to neglect training.
In this fanfiction scenario, Naruto might learn unique chakra control techniques from Sarutobi. Sarutobi, being an experienced ninja, could teach Naruto how to better manage his large chakra reserves. This would lead to Naruto being able to perform jutsus more efficiently and with less waste of chakra.