I want to know about entrance exam of B.Sc. (maths) syllabus and what type of questions asked in this exam.

Different universities follow different patterns with varying difficulty levels and weightage. In some universities like DU, you do not have entrance exams, but cut off %. Most questions are asked from 12th math, trigonometry, probability, matrices and differentiation, integration etc.

There is no entrance for B.Sc. You should complete your 12th with min 60% and you are eligible for this course.