[gambiting]

I don't know about India, but in UK if you have a notice period on your contract and leave before it's served, then the company can totally sue you for the work you promised you would do and didn't. So yes, a company can totally say "you can leave right now without working your notice period, but you need to pay us the equivalent of your salary for that time". Or they can say you can't leave until you worked the last day of the notice period - it's their right and something you have agreed to in the contract.