Options strategies

can we close all positions before expiry?
have any one traded in nifty strategy?

[1] Yes. We can close all positions before expiry. At any time we can close any position or all positions.

[2] No. I have not traded in nifty strategy.

Thanks tomjerry,
can we trade options strategies in sharekhans account?

I don't know anything about options strategy. But I know that you can trade options strategy in any account and even in sharekhans account. Each broker has different funda.