Hello,

You can do LLB after Bcom as its eligibility criteria is candidates should have passed Bachelor's degree in any discipline from a recognized university with 45% marks, for reserved category it's 40%. There's little bit of variation in terms of aggregate among universities as DU & BHU require minimum 50% marks while other Universities Kurukshetra, Rohtak, Meerut require merely 45% marks in graduation.

Some of the top universities which conduct admission for LLB through entrance tests are mentioned below;

DU LLB conducted by Delhi University,
BLAT by BHU,
LAT by Allahabad University,
LSAT scores are accepted by many reputed universities,

We also have state specific LLB entrance tests conducted for admission in various colleges and universities such as TS LAWCET in Telangana. AP LAWCET in Andhra Pradesh, MHT CET LAW in Maharashtra etc.