does he have any power?
Yes. He can  easily overcome any opponent that tries to fight him. He can also use all 4 elements at the same time.
The Avatar State
As his predecessors, his most powerful ability is the Avatar State, in which he receives a massive boost in raw power from the cosmic energy, enabling him to easily overcome any opponent that tries to fight him head on. It allows him to use all four elements at the same time. 
is avatar aang in the legend of korra Yes. Voiced by D.B. Sweeney what exactly is this avatar? It is a fictional character and the protagonist of Nickelodeon's animated television series what is the personality like? He is a vegetarian, reluctant to fight and kill
He is an incarnation of the "Avatar", the spirit of light and peace manifested in human form. As the Avatar, Aang controls all four elements (water, earth, fire, and air). Yes, he controls all four elements (water, earth, fire, and air) He receives a massive boost in raw power from the cosmic energy, enabling him to easily overcome any opponent that tries to fight him head on.
Aang Aang Aang
Introduction Introduction The Avatar State
He is an incarnation of the "Avatar", the spirit of light and peace manifested in human form. As the Avatar, Aang controls all four elements (water, earth, fire, and air) and is tasked with bringing balance and keeping the at peace Aang controls all four elements (water, earth, fire, and air)  As his predecessors, his most powerful ability is the Avatar State, in which he receives a massive boost in raw power from the cosmic energy, enabling him to easily overcome any opponent that tries to fight him head on
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Aang [SEP] The Avatar State
As the Avatar, Aang is as a bridge between "Material World" and the "Spirit World", the plane of existence where the universe's disembodied spirits dwell. His spirituality training progressed swiftly, granting visions and access to the various memories from his past lives. As his predecessors, his most powerful ability is the Avatar State, in which he receives a massive boost in raw power from the cosmic energy, enabling him to easily overcome any opponent that tries to fight him head on. It allows him to use all four elements at the same time. In addition, this state allows him to access bending techniques he would not have learned during his own lifetime but throughout those of his past lives.