Suppose the weapon is a flute. Naruto could use it to control summons or even manipulate the chakra flow in his surroundings. He might be able to play certain tunes that can either heal his allies or put enemies in a trance. This would add a whole new dimension to his abilities and make him a more versatile fighter.
Let's say the weapon is a shield. This would change his fighting style completely. Instead of always being on the offensive, he can now also focus on defense. He could use the shield to block powerful jutsus and then counter - attack when the enemy is vulnerable. It will also give him more confidence in battles against stronger opponents.
If the weapon is a blade, it will probably make his taijutsu more lethal. He can combine his already impressive speed and strength with the weapon's sharpness. His attacks will be more precise and deal more damage.
If the weapon is a chakra - enhancing tool, it will boost Naruto's existing jutsu. For example, his Rasengan could become more powerful, being able to break through stronger defenses.
With his mentor figures like Kakashi, they would likely try to guide Naruto on how to handle this new discovery. They would caution him about the potential dangers and help him understand the responsibilities that come with possessing such an ancient weapon.
His friends might be a bit wary of the sentient weapon at first. Sasuke, for instance, might be suspicious and think it could be a danger. But Naruto would try to convince them that it's okay. Over time, if the weapon proves useful, they could come to accept it.
Well, it could be a sword with the power to cut through any jutsu. Maybe it has some special markings that only Naruto can understand. It might also be a staff that can control the elements in a unique way, giving Naruto an edge in battles.
It could also change his stealth abilities. Since it's a shadow weapon, it may allow Naruto to blend into shadows more easily, making it easier for him to spy on enemies or launch surprise attacks. This would be a great advantage in his ninja missions.
Another way could be through inheritance. Maybe it was his father's or some distant relative's weapon. However, it was sealed away for safety reasons. As Naruto grows stronger and faces greater threats, the weapon reveals itself to him. It's as if the weapon senses that Naruto is the right person to wield it at that crucial moment.
Perhaps it's a staff that amplifies the user's chakra and also has wizard - like spells inscribed on it. The staff might be able to summon mythical creatures from the wizarding world to aid Naruto in battle. It could also have the ability to teleport Naruto short distances, which would be a great advantage in combat.
On the positive side, it might inspire new technology in the ninja world. The unique energy and design of the lightsaber could give the ninja inventors new ideas. For example, they could try to create a similar type of weapon that uses chakra instead of the lightsaber's energy source.
If the summoning contract has a connection to a particular family in the village, it could improve Naruto's standing with that family. He might be invited to their family events and be seen as an honorary member. However, if the contract is related to a dark or secretive part of the village's past, some villagers might be afraid of Naruto and try to distance themselves from him.
It could speed up his training significantly. If the jutsu scrolls contain advanced techniques, Naruto can learn from them and gain new skills faster than just relying on his regular training with Kakashi. For instance, if there's a jutsu for enhanced strength, he can add it to his arsenal and become stronger in combat.