The screenshot included in the question contains a block of text with a long interpretation by someone named Gary Moss. Moss's interpretation is that packs of wolves have alpha animals, which go in back, while older, weaker animals go in front. Supposedly the alphas "control the whole group" from behind.
The whole concept that a wolf pack is led by an alpha animal turns out to be incorrect. The alpha concept was based on studies of animals kept in cages, where they don't behave normally. It was debunked in a 1999 paper by L. David Mech. Here is the abstract of the paper:
The prevailing view of a wolf (Canis lupus) pack is that of a group of
individuals ever vying for dominance but held in check by the "alpha"
pair, the alpha male and the alpha female. Most research on the social
dynamics of wolf packs, however, has been conducted on non-natural
assortments of captive wolves. Here I describe the wolf-pack social
order as it occurs in nature, discuss the alpha concept and social
dominance and submission, and present data on the precise
relationships among members in free-living packs based on a literature
review and 13 summers of observations of wolves on Ellesmere Island,
Northwest Territories, Canada. I conclude that the typical wolf pack
is a family, with the adult parents guiding the activities of the
group in a division-of-labor system in which the female predominates
primarily in such activities as pup care and defense and the male
primarily during foraging and food-provisioning and the travels
associated with them.
Mech, L. David. 1999. Alpha status, dominance, and division of labor in wolf packs. Canadian Journal of Zoology 77:1196-1203. Jamestown, ND: Northern Prairie Wildlife Research Center