Yes, you can apply for CLAT exam. According to the notification you need to have passed your Senior Secondary School Examination/ 12th Board Examination for applying. So by the time the CLAT results are out and admission starts next year, you would have hopefully completed your 12th boards. Although you need to have a minimum of 45% marks in your board exams for being eligible for the course. SC and ST candidate need 40% marks.

The application form can be filled from January 1 to March 31, 2020. All the best.