A lot of people are saying that they can't do stuff do to lack of a credit card but you're wrong. You see there are "Prepaid Credit Cards" that are basically like gift cards, but you can spend them anywhere.
For example.
You need a credit card, but you're only 15, and your parents refuse to let you use theirs.
Go to a mall/bank/somewhere that sells prepaid credit cards.
They will usually ask for about 10% more than the amount on the card for the card. (A card with $50on it costs about $55)
Buy it, you now have a credit card with $50 on it, and you're under 18! Wooo.
Oh, and also, look for Visa cards, because they usually are more flexible for online payment (you can use them for your paypal and other things).