Just been given a tip for the best prepaid foreign currency debit card available, Revolut.
It’s a bit limited for cash withdrawals but great for using in shops and restaurants. Exchange at bank rates, no loading and no charge for using the card. You have to set up the account, very easy, make a small deposit and apply for the card, 5 pounds and then you’re good to go. You can “feed” the card as you go so there is no need to tie up lots of money on it. It’s recommended by Martin Lewis and managed through an app on your smartphone.