Attached is a picture of a hairstyle commonly used in Fallout game. The problem is I do not know the word to describe this hairstyle (the name of the hairstyle) in the real world. The difficulty comes that the hairstyle is named two different things in Fallout 3, Fallout New Vegas, and Fallout 4 (to my recollection). I believe it's known as the raider hairstyle and the urban ranger hairstyle. Attached is a picture. It is known for having the sides of the head shaved with the top being significantly longer and draped over one side.
It's called an undercut. In your picture, the sides have not been blended into the top, which is a common variation. The length is rather independent from the sides and back being shaved.
When requesting the cut, you can get the sides blended (which will slowly vary the hair length into the top and is not what is in your picture), you can choose the length of the shaved portion, and you can specify the length of the hair on top and many other attributes. The way the hair drapes is a matter of styling once the cut is done, but a barber or hair dresser may have advice on some of the finer details based on how you intend to style it.
the Pompadour Haircut theidleman
Swept back hair on men has always had a sophisticated, refined vibe, and there’s no better way to embrace this look than to try out a pompadour cut. They’re many different variations to choose from, and as you’re essentially just working with long hair and short sides, you can vary up the lengths so long as there remains a contrast between the top and sides... (more)
The variations of the cut in men are many. Interestingly this style is named after chief mistress of Louis XV, Madame de Pompadour. (18th century) It popularity is back in vogue with men (doubt you will see many women sporting the 18th style though)!
Most hair styles among men have military origin.
Among the American Indians of the today’s northeast US it was a sign of strength to have long hair.
However when it was time to go into battle the long hair interfered with the operation of the bow so it became necessary before going into battle to shave the head on the side that pulls the bow string back so long hair would not get tangled. The fellow pictured if he were a Mohawk Indian would be right handed as he has shaved the right side of his head.
The hair cut could be called a Mohawk tho it is not exactly like the punk style popularized in the 1970s.
One of my family members spent most of their life as a professional hair stylist. They said it would be referred to as a mohawk. The answer provided by @AllInOne gives good background on the etymology.
It is considered a mohawk since the side(s) are shaved and the hair runs all the way down the back of the head. More specifically, it may be known as a layered long mohawk, due to different "layers" of hair length.