Query about futures

Say I bought 1 lot of Reliance at 2409.85.
Against that, I sold an 2400 ITM call at 57.7.
I let those expire.

What will be the margin required in the fut contract as of the expiry day? Will it be 50% of the contract value?

How will the contract be settled? Will I be assigned at 2409.85 and the same stocks be taken away at 2400?

Will all this process be automated at your end, so that even if I don’t have cash to buy 1 lot of Reliance and neither have 1 lot to deliver, I wouldn’t be in trouble?