She is not supposed to use a Visa Waiver to enter the U.S. if her intention is to stay. So it is dangerous for her to do that. They may not let her in. IF she can somehow get in, then 60 days later after entry, you can file the following forms for her:
I-130 (Petition for family member), I-485 (application for Lawful Permanent Residency), I-765 (Application for work permit), I-131 (Application for Advance Parole), G-325a (Biographic data - one for each of you), I-693 (Medical exam that a certified doctor must fill), and I-864 (Affidavit of support). You will need to file each form with supporting evidence and appropriate filing fees. You can find these forms at www.uscis.gov/forms.
The supporting evidence that you would file would be birth certificates, marriage certificate, divorce certificates if either of you have been married previously, proof of your U.S. Citizenship, proof of your spouse's legal entry into the U.S., and financial documents to prove your income over the last year at least.
She does not have to leave the U.S. during this process and she should NOT leave until at least the Advance Parole is approved.
In about 3 to 5 months after filing, she should get a work permit and Advance Parole. About 5 to 7 months after filing you should get a marriage interview. If all goes well, a few weeks later she should get a Residency status (green card).
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