He leaves Ralph's group in Chapter Eight: Gift for the Darkness on page 127.
At the beginning of the book, Jack spends most of his time in the forest to hunt for pigs an track them down.
Jack offered, "Ralph-- I'll split up the choir-- my hunters, that is-- into groups, and we'll be responsible for keeping the fire going-- ."
Jack accompanied by Roger and Maurice raid the shelters and steal Piggy's spectacles.
Jack tells his tribe that tomorrow they will go hunting for meat and that the rest of the boys can improve the cave and defend the gate against the others and the beast. He re…plies to their queries that of course they didn't kill the beast and advises them to leave it the head of their kills if they go hunting. Jack also informs them that he will go during the night with Roger and Maurice to take fire from the others.
Ralph asks Jack "Why do you hate me?"
There are no arguments in chapter 1: the Sound of the Shell. Jack makes a few statements which are at odds with other boys and disagrees with some points but he doesn't argue …about anything. His biggest contention in chapter 1 is over who should be leader, when he suggests himself but is out voted by the majority of boys who favour Ralph.
Jack had two over riding obsessions in Lord of the Flies. Jack wanted to be leader and he also wanted to hunt (and kill) pigs. Jack had devised a new strategy which involved h…aving his hunters form a circle into which a pig could be driven and beaten to death. In order to put his plan into action Jack decided that he also need the two hunters who were on fire duty. As a result of this the fire went out, as there was nobody on duty to feed it with fuel. The real issue was not that Jack was thoughtless or negligent but that Jack though only in terms of himself. He wanted the boys on fire duty to join his hunt and that was all that mattered as far as he was concerned.
I presume that you are referring to the start of chapter 3: Huts on the beach where Jack is alone in the forest. The answer is that Jack is trying to hunt pigs.
Tracking a pig on all fours on the forest floors looking for all signs of an animal being present such as foot prints and feces (poop)
In the beginning of chapter three, Jack is hunting for hogs/pigs.
Jack was wearing a pair of tattered shorts held up by his knife-belt.
How to go about hunting the beast.
He is hunting for pigs.
You should probably read the book instead of asking the Internet to do your homework for you. Reading is good for you as a human being, you won't regret doing it :)
He is camouflaging himself so he can hunt without being seen