Can I apply though early action after being enrolled

You will be applying for Fall 2024, by which time you will have completed a whole year of college. IMO you’ll be a transfer applicant, not a freshman applicant. But there may be exceptions I’m not aware of.

Tagging @MYOS1634 who’s familiar with international applicants.

Most U.S. schools (other than those with rolling admissions) won’t provide you a decision until December or January, if you apply early action. And at schools where you apply regular decision, you won’t hear back until March.