Can I change my status online or should I go to the immigration in person?

If you are now married, the next step is for you spouse to petition to for permanent residency. I strongly 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, advise you of your options and make sure that the necessary paperwork and documentation is presented so as not to delay the process.

You cannot change your status online, and a personal visit to the USCIS will gain you nothing. You wife has to file an immigrant petition for you (Form I-130). It should be filed together with your application for adjustment of status (Form I-485), employment authorization (Form I-765), advance parole (Form I-131), and your wife's affidavit of support (Form I-864). All these forms can be found at uscis.gov, along with the instructions for each form. Technically, one is supposed to be able to fill out and file all these forms just by following the instructions. Most people try - and go to an immigration attorney for help. The rest go to an immigration attorney after their done-by-themselves applications get denied and $1490 in filing fees paid to USCIS, lost.

You can still apply for adjustment of status even after the 90 day period (as long as you married within the 90 days of your entry).

After marrying your fiance, you can now apply for adjustment of status with USCIS. The application is filed on form I-485 along with form G-325A, and the filing fee is $1,070.

You cannot change your status online. However, if you did get married to your US citizen fianc?, you can now file for adjustment of status on the basis of marriage. Please let me know if you have any additional questions or how I can be of further assistance to you in this matter.