Taxation query on FNO trading

AFAIK , we have to pay 30% tax on earnings from FNO trading , any way of reducing such a big percentage ?

You have to pay 30% only if you are already in the highest tax paying slab (<2.5lks no tax, 10% for 2.5 to 5lks, 20% from 5 to 10lks, and 30% for all income above it). You can invest into tax saving instruments to get the respective reductions that every person can. Also with trading as a business, you can show all costs incurred towards trading as an expense to reduce your net income. Suggest you to go through

https://zerodha.com/varsity/module/markets-and-taxation/

It’s almost 35.5% with surcharge and other things if your income exceeds more than 50lakhs or 1 crore. To reduce it, Don’t make more than 10 lakh rupees.