Do not use your parents debit cards, or any friends, as there is a bank statement history that will just have the manufacturer you used attached to it, which they can trace or your friends parents can trace. Try and use your own debit card or save money to put on a debit card because no adult store will sell to a thirteen year old, unless you have some kind of really good fake ID that says you’re at least 16+. Most manufacturers, like lovehoney or adamandeve have really discreet packaging where it’s just a plain brown box and maybe stamped with your address; I know when I’ve ordered from lovehoney before, I’ve been confused on what I may have got before opening it, since there’s literally no logo printed. Do your research and find a specific toy that will help you explore but not be too much, if it is your first time. In terms of hiding it, the best way I can say is get to it before your parents do, or buy something inconspicuous with them in a different package, so you can show them that if they ask instead. If your parents ARE nosy and suspicious, they’ll most likely check where you’re hiding it if they sneak into your room - usual places are the dresser drawers, nightstand drawers, the wardrobe and under the bed or your pillow. Places I don’t think they’d expect it to be are in a bookcase (in a box) maybe, your school desk if you have one in your room or at the top of your wardrobe in comparison to the bottom. Never take massive measures to hide them like wrapping them in a bunch of fabrics or being super secretive about where they are if they ask about it; a lot of times, hidden in plain sight is a good trick, though risky with sex toys. And, if you feel like you can at some point, talk to your parents about it slowly, as I’m sure they’d be more happy to know their daughter is being safe and trusts them rather than the opposite.
Stay safe, stay informed and if you end up using these with a partner, make sure they know your boundaries. Your safety and comfort is worth more than anyone elses orgasm.