Bihar Board (BSEB), Class 12 Computer Science Syllabus can be accessed in the link provided. Mind this is for session 2019-2020 and may differ for other session, with a minimal chances of change. Computer Science Syllabus (https://drive.google.com/file/d/1Vq7yzn3W3cLilcwUM2-iUwqZm4HKNBYJ/view)
For this you must have Class 11 Computer Science as a pre-requisite knowledge.
Thank you