Red Hulk in the comics is General Ross after undergoing some kind of transformation. He's got immense power and is a force to be reckoned with. His appearance and abilities differ from the classic Hulk in several ways.
It depends on the situation. Naruto has his powerful ninjutsu like the Rasengan and Sage Mode which give him a lot of combat power. But Red Hulk has incredible strength and durability thanks to his gamma - irradiated body. In a long - range battle, Naruto might have the upper hand with his jutsus. But in a close - quarters, brute - force fight, Red Hulk would likely win.
One of the best Red Hulk stories is 'Hulk: Red & Green'. It shows the intense rivalry between Red Hulk and the original Hulk. The battles are epic and it delves into the mystery behind the creation of Red Hulk.
The Red Hulk is the result of a transformation. Some scientist or villainous force experimented on a character to create this powerful and angry version.
Sure, She-Hulk is related to Hulk. Jennifer Walters, aka She-Hulk, got her powers because of a blood transfusion from her cousin Bruce Banner, who is Hulk. This connection is a key part of their storylines in the comics.