If they are an adult their status is still the same, they are an illegal alien.
No. The process is the same as it would be if the spouse were a U.S. citizen.
The same way one can get married in any other state
Firstly, there is no same sex marriage in Tennessee. If you are homosexual couple you will not be allowed to marry. Other than that there is no prohibition as to whom you marry. You can marry anyone you like as long as you are not of the same sex and under age.
Sometimes. The immigrant must follow the same procedures and apply for the green card. Often, they must voluntarily return to their home country to wait for their visa and permission to come through.
Follow the same procedure as if the person were a citizen rather than an illegal immigrant. File the dissolution of marriage petition in the proper court in the state where the person wishing the divorce resides.
The process is the same for marrying anyone, regardless of immigration status. There is no citizenship requirement for obtaining a marriage license marriage in Missouri.
Yes. None of the jurisdictions in the United States that permit same-sex marriage have a citizenship requirement for the marriage license. The couple must appear in person to apply for the license and show identification sufficient to satisfy the issuing authority. That ID can certainly be a foreign passport. Tourists frequently marry in foreign cities. The clerk will not examine the entire passport to see if there is a valid U.S. Visa and, even if he/she did, the absence of legal immigration status does not justify denial of the license.
Yes. A same-sex registered partnership is treated the same as a legal marriage in Germany with respect to immigration law. The same-sex partner of a German citizen can obtain legal residency and, ultimately, citizenship in Germany.
Yes. Beginning June 26, 2013, an American citizen may sponsor a same-sex spouse for permanent resident status.
In many places, it still is.
Most states have an age of consent for sex, and an age of consent for marriage (which may be the same of different). If you are above the age of consent for marriage then you can marry him. If not even with your parent's permission it will likely not be recognized as a legal marriage by the USA. Be warned, marrying an illegal alien is not a guarantee they won't be deported.