Iam not prepared entrance exams
Do not worry, if you are not prepared for the entrance exams its okay, just take your time, if you can take a drop for 1 year, then go for it, otherwise just do self-study and give your exams, who knows if you would be selected.
Commonly, entrance exams have a syllabus similar to your 11 and 12 classes. So if you know the basic concepts well, then you will qualify the exam.