USCIS offers different Green Card Eligibility Categories. For your information, you cannot apply for a Permanent Resident Card unless you are eligible under one of the 8 different categories.
The first possibility is to get a Green Card through family. So, you can apply for Permanent Residency if you are a spouse of a United States citizen, or the unmarried child under 21 years of age of a United States citizen, or the parent of a U.S. citizen (if the U.S. citizen is at least 21 years old). Other categories can be through family-based preference, fiancé(e), widow(er), among others.
Green Card through employment
This is the best category for those who are immigrant workers, immigrant investors, or for physicians (physician national interest waiver). Therefore, there are many immigrants who may be eligible for it in the first or second option.
Getting a Green Card through a special immigrant category is another possibility. For example, if you are a religious worker, a special immigrant juvenile, an international broadcaster or an employee of an international organization.
A category many people have heard of is the one for refugees or asylum seekers. So, check if you qualify for Refugee or Asylee Status. If you are a victim in a foreign country, there are also 2 more categories.
Green Cards through other categories
One of the most well-known categories in this section is the Diversity Immigrant Visa Program. People often know it as the Green Card Lottery. To be eligible under this category, you must have been selected for a diversity visa in the Department of State’s diversity visa lottery.
Check this category at the USCIS official website because there are too many different categories that may allow Green Card applicants to get a Permanent Resident Card in the USA.
The last option to get a Green Card is through registry. As a matter of fact, you may be eligible for it if you have lived continuously in the United states since before January 1, 1972.