Paypal is available as a payment method for the Shopify subscription if your store is located in any country other than the United States. If you are in the United States, then the only supported payment method available is a valid credit card.
If you’re in the United States, then I would recommend contacting your bank to determine if you can enable online purchases for your card. Alternatively, they may be able to offer a credit card that you can use for online purchases. If not, you can also choose to use a friend’s or family member’s card to place on the account then transfer them the funds at a later time.
I want to complete activating my store using PayPal. BUT, as soon as I press pay with PayPal it requires a credit card to be linked to my PayPal account although my balance is more than enough.
I live in the United Arab Emirates which from your latest reply seems it doesn’t require a valid credit card.