It's not possible to add funds into or Top Up a PayPal account with a debit or credit card. The only time a card can be used to add funds into an account is to pay a negative balance, and even then, the amount that may be added is limited to the amount the account is negative (bringing the account to a zero balance only).
It is possible to add funds into your account at a Walmart customer service counter. If you have the PayPal Cash debit card, adding funds into your account will also fund the Cash card because that specific card is directly linked to your available account balance. I'll link details below.