are these gcses good for medicine?

Not all medical schools score GCSEs and quite a few (e.g. Imperial and UCL) just require minimum grades in English language and maths (sometimes science as well). I would recommend focusing on medical schools with minimum grade requirements rather than those that score GCSEs formally and are quite GCSE heavy as a result (e.g. Cardiff and Oxford).

In terms of resits I think usually GCSE resits aren't much of an issue? As long as you meet the minimum grade requirements for those that have them. Perhaps for the GCSE heavy medical schools they might consider if they're resits more but as above, would recommend avoiding those anyway.

If you go into medicine your GCSEs and A-levels will cease to be meaningful once you earn the medical degree, at present. The only provider of graduate medical training posts is the NHS and they don't score any of that. Foundation post allocation is not more or less random I gather as well and I don't even think they factor in your medical school decile for that! Specialty recruitment might consider your medical school decile but GCSEs and A-levels are irrelevant. I seriously doubt they would matter if you are moving to another country to practice medicine either (although if that's the goal you should just aim to medicine in that country to start with usually!).

Outside of medicine also, just for general reference, GCSEs are basically meaningless if you have passed maths and English normally, and most graduate jobs don't have A-level requirements or cut-offs. It's just a handful of e.g. "top" law firms and in investment banking and such which might expect applicants to have achieved e.g. AAB at first attempt or something minimum. GCSEs are still a non-factor if you passed English and maths.

So would you say the ones that score GCSEs highly are only for those who achieved all 8s and 9s?