Hey.
The minimum requirement to become a corporate Lawyer is to compete a Law degree. It can be a 3 year law degree after graduation or a 5 year integrated law course like BA LLB, BCOM LLB etc after Class 12th.
Normally further specialisation or masters in the corporate field after completion of Law degree is not required. You can enter the corporate field even after completion of your basic Law degree. But In case you want to pursue further masters or specialisation there are various course like LLM/ PG Diploma in-
Corporate Law
Mergers, Acquisition and Corporate Law
Company Law
Trade Law
Commercial and Corporate Law
Similar courses are available in various law school all over India as well as Outside India which you can choose to pursue for further Knowledge and specialisation. Even though you can go for the Corporate field without any futher course.
Various Law colleges in India provide Campus Placements. Like CLAT is an entrance exam for admission in five year Integrated course of law like BA LLB, BCOM LLB, BBA LLB etc.
Also , CLAT is an entrance exam by which you can get admission into all the National Law Universities In India except NLU Delhi. Thus, if you get a good rank in CLAT you will get admission in of the top institutes of Law like NLS bangalore, NALSAR Hyderabad, NLIU Bhopal, NLU Jodhpur, NUJS Kolkata etc. Hence your scope of career will be very vast. Other than this National Law University, Delhi, Symbiosis Pune, Jindal Global Law School, GLC Mumbai, ILS Pune, Delhi University  and various other such law schools provide good placements.
Various top law firms, Multi National companies, Private companies like AZB Partners, Amarchand and Mangaldas, Trilegal, Surana and Surana, Dua and Associates, Khaitan, Luthra and Luthra and many tops Multi National companies like KPMG etc also place students. The packages offered to students of top tier NLUs and other top colleges  are very attractive. Many times foreign Law firms and MNCs have also placed students. Hence if you are interested in the corporate sector of Law, cracking these entrances and getting into a top law college should be your aim. You should try to aim for entrance exams like CLAT, AILET,MH CET, SLAT,LSAT, MH CET if you want to pursue 5 year integrated law course after class 12th. You should focus on  entrance  exams like DU LLB , MH CET, LSAT, SLAT etc if you wish to pursue 3 year Law after graduation. The syllabus for all of the entrances in quite similar, hence it won't be a problem. Only the level of difficulty as well as the vastness of syllabua would differ.
Other than this also you can make your way to right law firms by the right internships, moots, research papers and co curriculars.

Best of luck

Hello aspirant. Thanks for connecting with Careers360. You can undergo b.a llb course throug CLAT admission test. Corporate law is a specilization which you can opt in the final year of your degree. The basic requiremen of a corporate lawyer is a bachelors in law program. So, ba.llb is your option to become a corporate lawyer. I hope this answer helped you. Good luck.