How can my 20-year-old daughter get a green card through the EB-5 program?

It depends on which country/area you or your wife was born in. If the country/area is subject to a cut-off date, such as mainland China, India and Vietnam, then maybe not. If born in another country/area, you or your wife might be able to complete the process and have your daughter, who would be over 21 years old by then, be included as a dependent on your case under the Child Status Protection Act. If you are from an over-subscribed country, you might consider making your 20-year daughter the EB-5 investor.

It depends on where you are from. Mainland China, India, or Vietnam? If so then it is risky. Anywhere else could be OK. However, if you are really just doing this for her and her alone, just have her become the investor. Gift her the funds.

Yes, she will be protected, provided that you take steps to freeze her age under CSPA and your visa is not chargeable to a country that is currently or in the future an EB-5 backlogged country. Current backlogged countries/areas are mainland China, Vietnam and India.

Probably, but it depends on your country of birth.

Yes, she will be able to obtain a green card. It appears your question goes to the issue of aging out. However, the Child Status Protection Act (CSPA) protects children like your daughter from aging out. Thus, if you file your petition before your daughter becomes 21 years old, her age will be frozen, even though she may be over 21 while the petition is pending. Further, be aware that the frozen will continue to be in place two years after the I-526 has been approved. Advisably, consult with an immigration attorney on further details and analysis of your case.

You should file as soon as possible. Upon the filing of the I-526, the age of your daughter will be frozen and covered under the Child Status Protection Act while I-526 is pending. Provided you are not from a backlogged country, you should be fine.

Maybe she can, as the time it takes the CIS to adjudicate the EB-5 petition can be subtracted from her age at the time she applies for immigrant visa or adjustment of status.