It appears from your other questions that you are asking about the theory that holds that the ancestors of the Native Americans came to the Americas in three waves. This is a controversial thesis that is supported by some DNA and linguistic evidence but which is by no means universally accepted.
According to this theory, the first group to come to the Americas were the "Amerinds." These people got to the Americas about 30,000 years ago. As they have been here the longest, they are the most widespread. Their descendants are said to live in practically every part of the Americas.