What could happen is that Naruto's cold makes him more vulnerable to an attack from a hidden enemy in the village. The enemy could sense his weakened state and plan to kidnap him. However, Naruto's ninja instincts, even while sick, kick in and he manages to fend off the initial attack. This then leads to a full - on investigation to find out who the enemy is and why they targeted Naruto when he was ill.
He could start hallucinating about his past battles or his dreams due to the fever from the cold. His friends might get really worried and call in Tsunade to check on him. Tsunade could discover that Naruto's chakra is also affected by the cold, which leads to some interesting plot developments about how to get his chakra back to normal while also curing the cold.
Next, Naruto might try to tough it out and continue his normal routine, but keep making mistakes because he's not feeling well. This could lead to some comical situations, like accidentally using the wrong jutsu during a sparring session. Meanwhile, his friends could be trying to find a rare herb that is said to cure any illness quickly to help him get better.
In such a fanfiction, Naruto might return to the village with new and powerful jutsu. He could surprise his friends with his enhanced skills. For example, he might be able to create new types of shadow clones or have a better control over his chakra. Maybe he would also have new insights on how to deal with his enemies, like Orochimaru or the Akatsuki.
Well, Naruto might learn some new and powerful jutsus during the training trip. Maybe he meets some unique characters who teach him special skills or give him valuable advice.
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.
Well, perhaps in this fanfiction, Naruto would meet some long - lost clans or masters during his extended training trip. They could teach him ancient and secret techniques that are not known in the normal Naruto world. He might also form new and unexpected alliances with other characters. For example, he could team up with a group of wandering ninjas who have unique skills. And his training trip could also be a journey of self - discovery, where he learns more about his parents and their legacy, which in turn gives him more motivation and strength to become a better ninja.
In the fanfiction of their training trip, there are several possibilities. Naruto, being the energetic one, would probably push Hinata out of her comfort zone. They could meet some strange characters who give them unique training methods. For example, they might find an old hermit who teaches them a special type of chakra control. This would not only enhance their skills but also bring them closer as they face challenges together. Their bond would likely grow stronger as they rely on each other during this trip.
He could learn new and powerful jutsus. For example, he might discover some unique wind - style jutsus that are not in the original series. This would make him more formidable in combat.
He could meet an old hermit ninja who imparts his wisdom and knowledge to Naruto. This hermit might have been living in seclusion for years, but seeing Naruto's potential, decides to teach him things not found in normal ninja training.
One possible plot could be that Naruto returns from his training trip with new jutsu and a more strategic mind. He starts to outwit his opponents in battles, surprising everyone in the village. For example, he uses his newfound knowledge to defeat a group of rogue ninjas who were causing trouble near Konoha.
Well, it could be that the kid serves as a source of motivation for Naruto during his training. He would want to become even stronger to protect his child. Also, the presence of the kid could lead to some comical situations, like when the kid tries to imitate Naruto's training moves in a clumsy way.
During the training trip, they might face some tough opponents. This would force them to rely on each other and grow closer as a result. They could also discover new places with unique chakra sources that enhance their abilities.