23M, Need advise on how to retire parents.

My dad is 63 years old and has his own business. I just graduated 3 months back and am helping him with it. My parents have no idea about investing money. They still belong to the orthodox pedagogy that investing money in the stock market is bad. Currently, we are sitting on a corpus of roughly 30L and I need advice on how to grow this particular amount so that my parents don't feel the burden of not having enough money.

[Rough expenditure per month is around 17k for the whole family.
The business is quite dull this year.
If we had to put a number on the table, we make around 15LPA after taxes.
Parents have taken a LIC premium policy when matured, we get around 12L.]