You should hire a good criminal lawyer and fight the DUI charge. You should also consult with an immigration lawyer in your area.
The DUI charge may have a negative effect on your green card application. Several things could happen. One thing that might happen istThe immigration officer may continue the interview to see how the criminal case progresses.
You would likely receive probation, if you decide to plead to the charge. But, the immigratio issue is too important and you should try to fight it. Your criminal lawyer will advise you about how good your chances are depending on the facts of your DUI case.
The Okaloosa County Written Plea Agreement was substantially changed, and the section about deportation was put in boldface - this means get an experienced criminal defense lawyer. Don't handle this one yourself, too much is at stake.