Hi,
DU LLB programme comprises 20+ compulsory subjects and 20+ optional subjects. In my limited experience, I haven't come across any course such as LLB Taxation. However, according to the Revise Syllabus of DU LLB , Taxation Law is being taught to its' all students during the 6 th term as it has accommodated LB-604: Principles of Taxation Law as a compulsory subject.

I hope it helps!