Can I adopt even if I am not a legal resident in the United States ?

You cannot adopt in the United States if you are not a legal resident. Some states even require U.S. Citizenship to adopt. Fortunately, most states do not require citizenship, but they do require you to be a legal resident of the United States. This might mean that you have a green card or are living in the United States on a work or other long-term visa. California is one example of a state where you can adopt if you are not a citizen but you are a legal resident.