Major paypal help needed here * First time buying online*

Alright, I recently wanted to buy some zp. But unfortunetly the day before I wanted to buy some my mother cut up her credit card.So now I have a prepaid visa credit card with 50 dollars loaded on it.I want to buy zp with it,

The problem is that I have no idea how to use paypal, If I put my prepaid card on paypal how do i use the money on it to buy zp?Please help me.And also how do i put money on my paypal account with my prepaid.