I'm turning 18 in a month and want to get a new credit card (my current one is under my dad's name). I'd like to get a card with cash back (not rewards). I was looking at an Amex Blue, but the cash back isn't that high for low balances (I'll probably only spend a few hundred or up to 1000 dollars a month). What is the best card for me? Also, does Amex still do temporary card numbers for buying online? Thanks.