This is Naruto's fight with Kurama the Nine Tails. This is done so Naruto can take some of the Nine tails chakra for his own. I would recommend the hero route as you get support from Bee as a result. The Nine tails has various attacks; one being a mortar like strike of tailed beast bombs which is easy to dodge. Just watch the ground to see where they are coming down. If you cant get out of the way fast enough use a substitution jutsu to avoid harm. He also attempts to jump on you occasionally; just side step or use substitution to get out of the way. He also uses a literal version on the tailed beast ball; this travels in a straight line so its easy to dodge.
If you hit him with rasengan + it will send him flying back; giving you a chance to heal and charge up your chakra hold . Once you get him down 1 full health bar plus about 1/3rd of his second the Nine tails will attempt to finish the fight in a short cutscene. Bee catches the attack to protect you; this causes him to be unable to help for the remainder of the fight. This is inevitable and will happen no matter what. Once that has happened he will run around the outside of the arena shortly and then jumps back in to throw several straight line tailed beast balls at you. Dodging them with a side step is easy enough.
Hurt him some more and once his 2nd health bar is down to about a quarter left; a series of quicktime events will start where you knock down the Nine Tails and then make your first attempt at stealing some of his chakra. This ultimately fails and a cutscene ensues with Naruto's Mom.
Once the cutscene is over the battle resumes. This time the Nine tails is partially chained up with Kushina's (Naruto's Mom) justsu and she will now act a support for you. During this bit you have limited chakra, its enough for multiple rasengans though. Now as long as support is available you can use it to have Kushina enforce the chains and stop the attack. Giving you a chance to land 2-3 rasengans + with no resistance. His attacks are now shooting 3 quick tailed beast bombs (easy to dodge), swiping his claw at you (easier to dodge) and a version of the tailed beast bomb that is a giant beam that reaches the length of the field. When he does this you really have 2 options run to the left and outrun it or substitute out of the way and let it pass.
Once his health gets low on the 3rd bar he starts getting really angry. He starts using an an energy slash attack that come in groups of 4. Easy to dodge as you can get between them or move to the side very easily. He also starts pounding the ground to have a tremor wave try and hit you; simply jump over it by hitting as it gets close. After a few rounds of attacks he will worn out and you can attack him on the face.
Then he will start to come at you with one his tails; very easy to dodge as you can see where its coming down. Once it gets stuck in the ground you will get a prompt on his tail you press . This will start a quick time event where Naruto successfully pulls out some of the Nine Tails' chakra. after that you will be able to use your ultimate jutsu in combat. Use it once by hitting ++. This does some good damage and also leaves the Nine Tails worn out. Hit him a few times with the rasengan to trigger the final set of quick time events. This ends the fight; if you have a majority of your health left you should get your S rank.