Yes, you can go back to your alma mater to re-register for the college entrance examination, or take the adult college entrance examination, but I suggest you go back to school to re-study, because you just graduated from high school for one year, it is still ok. The college entrance examination is a unified recruitment and belongs to full-time. So I suggest you go back to your alma mater and ask about the specific procedures. I wish you success in the college entrance examination in the future. If it helps you, please adopt it!