Yes, you can, but please note that when you register your card with PayPal, a preauthorization is carried out to make sure your card is valid. This means PayPal block a small amount on your card (usually £2 or less) to check that there is an available balance.
The preauthorisation expires after 14 days and is never collected from the card. Make sure you have at least £2 in your balance if you are going to register it with PayPal.