My recollection is that you must have sufficient Venture Miles to cover the entire amount of a specific travel transaction. However, you can also redeem for gift cards at the same rate $0.01 per mile. There's no particular reason to choose one type of redemption over another, the financial outcome is identical.

You can use Search this Forum to look for previous discussions of this card, but note that the name of the bank is spelled with an "a" (Capital) rather than an "o" (Capitol). Look also for these variants: CapOne Cap1 C1 and Venture.