If you are selected for group Y or X, you will be called as Airmen. It is a post of non commissioned officer. As you know this Group X and Y exams are for 12th completed Candidates. To become an officer you must atleast have a bachelor's degree with 60% and above. Then you can apply for Afcat and after clearing that you will have to clear AFSB, and after that you will be selected for a training in AFA, after completing 1year training you will be commissioned as an Officer. But directly through Group X and Y you cannot become an officer you will have to go through this process.