It's a shuttle tanker. Used for shuttling crude oil from the offshore oil fields in the North Sea to terminals around Europe.
In norwegian terms they are called "bøyelaster", or "buoy loader" in english.
Simply because they load from a buoy in which is connected to a storage tank at the offshore platforms.
They connect the loading hose in the bow. The arrangement in the bow is called BLS - Bow Loading System. On this particular vessel they have a bow house where all the manouvering when approaching the buoy and during loading is done.
On newer shuttle tankers all the manouvering and loading of the vessel is done from the bridge. At all times when approaching, connecting, loading, diconnecting and leaving the field, the vessel is on DP - Dynamical Positioning.