move overdraft & personal loan to 0% interest credit card??

OK - taking your points, questions one at a time then.

Just because you have in the past been "rubbish with your money" doesn't mean you have to stay that way. Being blunt, what you actually mean is "I'm too lazy to sort my money situation out" - so for a long term fix look to treat the cause of the problem, not keep sticking a plaster over the problem itself, would be my suggestion. A bit of effort now = a situation going forwards where you can proudly say "Yeah, I'm pretty good with money, actually" which is a good feeling, I promise.

Your debt might not be an outrageous sum to some people but it sounds like you're a bit uncomfortable with it - which is a great reason for sorting it out. It's also enough, I'm guessing, that if you lost your job tomorrow, it would cause you a bit of a panic, no?

0% cards are great BUT only if you don't then take on any more debt. If you do, you're setting yourself up for trouble, particularly if you don't actually have a viable working budget in place. "Rubbish with money" & 0% cards are NOT a match made in heaven - you need a good degree of organisation to juggle repeated 0% transfers without getting stung with interest and rising debt.

first question then: See above.
Second question: Not immediately relevant as a result of ^

I had a quick look on the credit card eligibility calculator and it only shows me 1 card that would approve me (this doesn't exactly fill me with loads of confidence).

No - this suggests that perhaps your credit history is looking a bit ragged, doesn't it.

Suggestion from me would be: Get yourself a budget sorted. You could use the SOA calculator we recommend on here (link is in my sig or in the sticky post at the top of the board) and actually go through all your outgoings so you know how much you should have left at the end of the month. Make it accurate and ensure you include everything. Old bank statements can be handy here. Remember things that maybe you only pay out for annually or a few times a year. Get the figures right - don't round things down - if you really must round then round UP. Once you have your working budget live with (and within) it for a few months - you could also post the completed SOA here if you wanted and we could see if there are savings you could perhaps make that you might have missed. Learn to stop and think before you spend - if you impulse spend on debit cards or contactless go cold turkey on them and use cash for day to day spending. Stop using the credit card - literally cut it up or shred it.

Initially: The surplus you have at the end of the month reduces the overdraft. Continue paying the loan and the CC payments as usual. Maybe think about setting the CC to a fixed amount monthly rather than just letting them take the minimum.
When the OD is cleared, the surplus goes to the CC. Keep paying the loan as usual.
When the CC is gone, divert all money to the loan so long as the terms allow overpayments.

If once a few months have passed you're getting on well with the budget and you have the surplus you should at the end of the month you could think about applying for the 0% card perhaps - but I really wouldn't do that until you're confident that things are under control.