There are three kinds of point of view: first person, omniscient, and third person limited.
To determine point of view, look at how the writer presents his character(s). Does the narrator refer to himself as "I"? If so, it is first person. Does the writer reveal the story through the eyes of more than one character? That would be omniscient.
"An Episode of War" is told through the eyes of the lieutenant. Everything focuses on his thoughts, feelings, and perceptions. Therefore it is told from the point of view of third person limited. We, the reader, are limited in what we can know by what the character actually knows.
Crane actually puts us in the head of the character with this line: "The lieutenant hung his head, feeling, in this presence, that he did not know how to be correctly wounded." But this is the only character whose thoughts are revealed. If Crane revealed thoughts of others also, he would be employing the omnisicent point of view.
By using the third person point of view, Crane directs his readers focus on the lieutenant, rather than the other soldiers that are also in the story. Their function is to be a part of the setting and to show the kinds of attitudes and behavior that the wounded lieutenant elicits from others.