Do I need a credit card to sell on Threadflip?

I tried selling on poshmark, but then I found out you need the iphone app to sell. And I don't have an iphone. I want to start making my own money since I'm 18. I can't get a job due to my schooling and such. So anyway for Threadflip you can sell clothes through your computer not only the app, but I was wondering if anyone has experience on it. And If I need a credit card or paypal?

You're an adult. Even if you don't have a job, your mom should help you in opening a checking account so you can learn. Part of good parenting.
i had a job at 15 and worked for many years while in school.