Even if you got a paying job (e.g. a paper round) to save up to buy one of those, you would still need to pay for it's ongoing use, whether pay-as-you-go or pay monthly. At 13, that's not going to be very affordable.
You will need help from your parents or older siblings. If you are not lucky like that, you will just have to accept the situation and either ask for something more economical or another solution.
