Regarding severance pay

A little background - I am working in Cognizant Technology Solutions India Pvt Ltd from past 7 years and currently deployed on bench. It's been around 64 days on the bench now & per organizational policy bench period is of 35 calendar days. The opportunities presented to me so far were either not relevant and out of the domain expertise or were scrapped, already filled by the hiring project. Company is constantly encouraging us to get upskilled/reskilled however even after getting so, the hiring managers needs relevant experience and don't end up hiring. Question - Now, the company HR is asking me to either voluntarily resign and get a normal exit or else will be terminated on grounds of "failure in the opportunities to secure work allocation and being in bench for a longer period without any work with full salary". I need an advise to understand which option would be best for me monetary wise as well as the future career wise. Will there be any difference in severance pay accordingly (voluntary resign vs termination). The HR is saying there will be no difference. I want understand things from the perspective of Law.