If my ICO hits the hard cap.
How can I withdraw the ICO funds into fiat currency? through the bank? how is this possible?
Your ICO? you mean you are the owner of the ICO or just a bounty hunter? You can withdraw your ICO funds into fiat currency once it is listed in an exchange. Its either will be paired to ethereum or bitcoin in an exchange. In localbitcoins.com there are so many bitcoin buyers near your place and you can get it directly into fiat via bank.