The short answer is: people like you! While the homes of the herders in the countryside may not look like yours, they are ranchers doing similar work to people who raise livestock in other places. People who live in the city work and play in ways that people all over the world would recognize.
Half of all Mongolians live in Ulaanbaatar, where about half live in apartments and about half live in gers, even in the city. Go to the page about Homes for more information about the kinds of places where people live.
About another 500,000 live in towns of under 100,000 people. That’s about the size of Evanston, Illinois; Carlsbad, California; Kalamazoo, Michigan; or Scranton, Pennsylvania.
The rest are primarily nomadic herders living on the wide grasslands. What does that mean? A herder is like a rancher in the American west or on an Australian cattle station. In Mongolia they raise some combination of goats, sheep, cows or yaks, and camels, depending on their resources and where in Mongolia they live.
They are nomadic because they do not live in one place all year round. They move from one area to another with the seasons, packing up the round tents in which they live (called gers) along with all of their possessions and their herds.
There is very little immigration into Mongolia, so most people would identify as Mongolian and speak the Mongolian language as their first language. There are some minority groups in Mongolia who speak dialects of Mongolian or other languages and whose cultures are different from the majority including the Kazakhs in the west and the Buryiats and Tuvans in the north.