Du aur bhu llb ke tayari kaishe kare
Hey.
You can use the following books to prepare for LLB for DU as well as BHU entrance test- Universal's guide for CLAT and LLB, Arihant's manual for LLB, Universal's compilation of previous year DU LLB paper with solutions. Other than that you should also take a look and solve the previous year question papers.
Best of luck!