How do balance transfer credit cards work?

I have debt I need to tackle and was told about 0% transfer cards. Are these cards only used when your debt is with other credit cards? Or can they be used if I owe payday loan lenders?
Basically my credit score is still good I was just wondering is it possible to get a card with £5000 and with 0% interest for 6+ months so I can pay this off as quickly as possible and rid myself of debt? How exactly do these work as opposed to standard credit cards / what is my best bet? Thanks in advance for any advice.

1) the credit limit you get is up to the lender and in today’s environment getting 5000 pnds is asking a lot for a new card. You are much better off if a bank will lend you money on an installment loan