Hello friend, the Kerala higher secondary syllabus is just that of CBSE.They prefer the NCERT books. But unlike CBSE you'll have 6 subjects in total,in which two are languages (English and other optional language according to the school). If it is vocational higher secondary they provide more combinations,but the syllabus are same for state and CBSE. When it comes to board exams, you'll have to appear for both years(11&12).But the exams are going to be a slight less difficult for you to score,than that of CBSE.

If you have any further query then let me kniw in the comments below.