Well, there are generally 5 avenues to obtain U.S. Lawful Permanent Residency. They are through family, through employment, through Asylum or refugee process, through investment, or through the lottery.
For family, it must be immediate family such as U.S. Citizen spouse or U.S. Citizen children over 21 in order to be able to come immediately. U.S. Citizen or Lawful Permanent Resident parents or U.S. Citizen siblings, or Lawful Permanent Resident spouses can also help you, but the wait for that is about 4 to 12 years or so.
Through employment, you would have to generally prove that you would not be taking away a job from a U.S. worker and the less experience and education you have, the harder that is to do.
Through Asylum or Refugee process, you must prove that you will be persecuted, tortured or killed if you stay in your country and that this will happen to you because of your nationality, race, religion, political opinion, or membership in a particular social group, not because you would run the same risk as anyone else in your country to fall victim to a crime or bad economic conditions.
Through investment, you are looking at generally $1,000,000.00 for a residency, or $500,000.00 in an area designated as a high-employment area, plus in both cases the investment has to create 10 or more jobs for U.S. workers.
And through the lottery, it would be very difficult to win one of the 50,000 visas available per year and some countries do not qualify.
Here is a link to the different forms to get a green card:
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