What is required to be done if an employee is terminated? How many days of notice to be given - as per law?

What is required to be done if an employee is terminated? This is a manufacturing company of medical instruments ophthalmic devices in New Delhi
How many days of notice to be given - as per law?
Is any amount to be paid of for further days extra then notice period.
As employee here is asking for months of amount to be given to him. Is there any law.
Please suggest it is urgent.

As employee here is asking for 3 months of salary to be given to him. Is there any law.

Answer depends upon the number of employee your organization has, Category of the employee who is terminated...
Reason of termination