Is there any strategy in trading f&o where I can get an assured (or partially assured) rate of return? Something like low risk with good returns

Assured return : Not possible.

Low risk and good return - try

debit option spread.

long strangle/straddle ahead of anticipated move.

all the best.

creat your own trading system and try Low risk and good returns

like this

There is no thing like assured return in stock market. Change your approach to “Low Risk high rewards” Probabilities that can give consistent gains on long run.