What was The effect to agriculture on the way of life of the early people?

Prior to an agricultural society, most primitive people lived a nomadic life. They were 'hunter/gatherers' who moved frequently to follow herds of animals. This meant that their food supplies were not consistent and it was not possible to store much food for Winter or any form of disaster.

Hunter/gatherers live a hard life and injury and death was common, but then as they started to settle, they were able to organise into larger groups. Doing so improved and increased food productivity and more food meant healthier people. Healthier people meant that the population could increase as the likelihood of starvation in times of hardship reduced.

An excess of food produces a community where some members of the community don't have to be farmers and can be freed to follow other pursuits. Specialisation in areas such as religion, health, and most importantly education produced new technologies further increasing the production of commodities. From the excess of these commodities sprang forth trade and communication. Trade leads to wealth and when that happens you see the emergence of the super rich in societies.

It's not all good though, the increase in size of towns and eventually states can create wars over the possession of land as resources dwindle. This scenario has been played out many times over history. Also a reliance of a large populous on farming can cause starvation when the crops fail, or the population exceeds sustainability as has happened in modern day Ethiopia.