Sorry for n00b question but is there an index like sensex or Nifty that includes the sum total of the entire stock market?

AMO orders before market open

If you’ve placed a market order, it’ll get executed at best available price in the market when the market opens at 9:15.

If you don’t have enough funds, your order will be rejected.

If you’ve placed a limit order at 280 and market opens at 320, then your order won’t execute. Limit order get executed at the price you’ve specified or better price, since you have placed buy order this will execute at 280 or lesser price.

Didn’t get this, can you elaborate?

You’ll only know the opening price once the market opens at 9:15, as for F&O there is no pre-market.

Buy limit order will execute at price you’ve specified or lower price. Your order will remain pending until it is executed.

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