How to invest the Terminal benefit received at the time of retirement?

I have retired from active service as Professor of Surgery after 34 years of service and the terminal benefit received is 30 lakhs. I am reappointed back with same salary last drawn which is about 1.25 lakhs per month. Both my children are married and are on their own.I do not have any outstanding loans to pay back.I am on my own staying in my own home. Please let me know the ways in which I should invest the terminal benefit amount of Rs 30 lakhs. I am not well versed in share market. I am sure this is common problem for all professionals at the time of retirement.I am sure I will be able to get a better information about investing the amount,as you are aware that Surgeons are very poor in investing for their future.