I attempted to link the card. PayPal was supposed to have sent a small sum or taken off a small sum from my bank account together with a line containing a code, but the bank showed no transaction, so I have no code and cannot perform transactions online using PayPal.
If your online card statement shows pending transactions you may be able to see the code within minutes. The code will be printed next to the word 'PAYPAL'. If not, check your card statement within 2-3 working days to find your 4-digit PayPal code beside, or near the 1 euro charge. If you can't check your statement online, you'll need to wait for your next paper statement or contact your bank.
Once you have the code, you can confirm your card as follows: