examples of peer presure as used in this novel,

Here are a few examples for you:

At the beginning, the old boar on the Manor Farm, Old Major,tries to convince the other animals that human beings are parasites.

Snowball manages to convince Mollie that her prized ribbons are “the badge of slavery"

The sheep show limited understanding of the situation but support Napoleon's ideals and they are regularly shown repeating the phrase "Four legs good, two legs bad".When ,at the end of the novel,one of the Seven Commandments is changed after the pigs learn to walk on two legs, their cry changes into "Four legs good,two legs better.”