How long can I stay with a tourist visa?

As a visitor for pleasure [tourist] in possession of a B-2 visa, upon arrival at a US port of entry, the Immigration inspector will at his / her discretion determine the period of your stay (after a short interview ). between for as short as 2 weeks to a maximum 6 months period. The actual date before when you are required to depart will be endorsed on your Form I-94 white card. If you intend to stay beyond the I-94 period, you must make a request for extension to CIS, before the date shown on your I-94. In most cases, you can extend your stay for no more than 1 year total. As an LPR, your mother can file a petition for you, but then, only if you are single. Such petition, under F2B category will not be current for about 8 years. You are not permitted to stay in the US to await the approval of that petition. If you wish to stay legally in the US for a period longer, then it must be under some other nonimmigrant visa category. After entry into the US, you can seek to change of status into any of the available nonimmigrant visa categories which will allow you to stay in the US for several years. Your eligibility for any of these visa categories will depend on several factors. You will need to consult in depth with an attorney who may advise you of your options.

You can stay in the US lawfully for as long as you are authorized to do so by the CBP officer at the port of entry. They will determine this based on what you indicate is the reason for your travel to the US. You should not indicate that you intend to apply for a green card as that shows immigrant intent and you will not be permitted to enter the US at all. Assuming you are permitted to enter, you will not be able to apply for a green card anyway since you are subject to fairly long waiting times as a son/daughter of a US LPR. The wait times are about 5-8 years currently, assuming you are not married; if you are married, your mother can only petition for you if she is a US citizen and the wait times are still about 5-7 years, and you'd have to be in lawful status at all times in order to qualify and, of course, you cannot remain in valid tourist status for that long.

You can stay for as long as your visa and I-90 allow, usually 2 to 6 months. With regards to you obtaining a green card, this question requires an attorney consultation. It is not a simple question that can be answered on this type of forum. There are many factors that would need to be considered and evaluated. When you are in the U.S., I suggest that you contact an experienced immigration attorney for a face-to-face consultation and give him/her all of the facts surrounding your situation. He/she would then be in a better position to analyze your case and advise you of your options.

Typically, the immigration officer at the port of entry will give you 6 months, but sometimes less. You can always file for an extension if you need to stay longer, but no guarantee it will be approved.

The longest that a visitor on a B-2 visa can stay in the United States is 1 year, but the CBP officer at the point of entry will actual determine how long you can stay in the U.S. If you are currently unmarried, your mother can petition for you but you will need to return to your home country to wait for the availability of an immigrant visa number. Depending on what country you were born in, the wait could be many years.