Hunter-gathers existed during the Patholithic age. Hunter-gathers got their food by hunting animals and collecting berries and other fruits and vegtables.
The agricultural revolution was hunter-gathers domesticating animals and making them into farm animals creating a stable food supply. The agricultural revolution happend during the Neolthic age. The types of housing were permanent housing.
Life improved for these hunter-gathers by having a stable food supply from the river ( fish ) and from farming (crops). Another way life changed is less people died because not many people went hunting. Another way life changed is that having permanent homes created more jobs such as farming and other jobs. Another way life changed is that they could trade because they had a stable food supply.