Failure to return the forms promptly will delay the processing of the visa application. The period of time it will take to process the application will vary with each individual's circumstances. If the U.S. Citizen is the natural father of the child, the child may have claim to American citizenship and, therefore, may be eligible for a U.S. passport. You are required to marry within 90 day of your arrival. After the marriage ceremony, you are required to apply an adjustment of status from nonimmigrant to conditional resident with your local INS office.
Conditional residence is granted for a two-year period.
A petition must be filed to have conditional status removed. The INS will advise further. To obtain employment authorization you will need to file form I-765 with the INS Service Center which covers your place of residence in the U.S after your arrival there.