The question of whether your marriage will result in a green card (legal permanent residency in the United States) is another. Nothing prevents you from marrying a U.S. citizen or almost anybody else if you are an undocumented immigrant in the United States (sometimes known as a "illegal alien"). However, there are several issues that could prevent your immigration attorney from filing papers on your behalf.
In order to be granted a visa for marriage purposes, the American government requires that you have a good reason for wanting to get married. Therefore, they will not grant a visa unless your marriage has something to do with citizenship or immigration status. For example, if you were convicted of a crime and sentenced to prison, a judge would be able to issue a special license allowing you to marry while you are in jail. If your spouse files a separate form called a "Form I-360" (because it contains both pages of Form I-130), this would be considered an "immediate relative" petition and could lead to your being given permission to enter the country.
However, even if your marriage meets the requirements for a visa, that does not guarantee that you will be allowed into the country. Every year, the U.S. Citizenship and Immigration Services (USCIS) receives many requests for visas, but only a few are approved. The decision on whether or not to approve your particular request is up to a single officer who reviews each case individually.
If you marry a US citizen, you will not be eligible for US citizenship immediately. However, you may be qualified for a US green card, which can lead to US citizenship.
In order to apply for a US green card, the immigrant in question must meet several requirements. They must be able to prove that they have enough income to support themselves and their family. They must also pass a health examination. Finally, they must show that they are likely to become citizens at some point in the future. The process of getting a US green card can take many years because there are so many people trying to do it. In fact, it is one of the most popular ways for immigrants to gain legal status in the United States.
When you marry someone who is already a US citizen, you will not be able to acquire US citizenship yourself. However, if you marry someone from another country then you will be able to apply for a visa for your new husband or wife. The type of visa that can be applied for depends on what kind of relationship the two of you have. For example, if you are married but live in different countries, a B1/B2 visitor's visa might be best for you.
You must meet several years of physical presence in the United States and pay federal income tax to become a US citizen.
The first step toward US citizenship is to file an application for a US passport. The application can be downloaded from the US Department of State website. You must provide proof that you have met all requirements to establish eligibility to apply for a US passport. This may include proof of having been physically present in the United States for a certain period or being a veteran of any branch of the armed forces. As well, your spouse must be able to support you (or be deceased) to be eligible for a passport. A social security number is required to file an application.
Spouses of US citizens can work together with the US government to facilitate faster processing of their visa applications. By becoming a "spouse" of a US citizen, your own status as a non-citizen will be recognized by the US government. This means that if you are living in the United States legally, you should be able to obtain a visa allowing you to travel to America.
In conclusion, yes, marrying an American makes you legal.