There are several advantages and all members benefit from them. The wolf usually hunts large prey, for example elk, reindeer and deer. It is easier to kill these preys if the wolves are several together. Also, it is easier to defend territory and the cubs learn the social life and hunting.
Only the parental couple has cubs. The younger wolves in the pack help to raise new cubs. It increases their survival and the pack's chance to subsist.
The female of the couple often protects the den and take care of the small cubs, while the male often leads hunts and bring food to the female and the cubs.