What do uni mean when they say they dont accept resits

If they accept resits you will be considered (if this is what you are asking, sorry the way you worded it is confusing).

It literally means they do not accept resits of examinations. No matter how good, they don't accept resits. Apply somewhere else or wait a couple of years and consider an Access course, foundation year etc and study as a mature student.

They ignore your new resits grades and look at first attempt or they would just straight on rejected coz you.

For context why im asking this is that i met the generla minimum gcse requirements first attempt for ucl med and imperial med but they accept resits. So even if i met it first attempt but ive resat would i still be considered or straight on rejected?

I dont have an extenuating circumstance

Firstly I would suggest you contact them to clarify if they mean GCSE or A-level resits.
If they do confirm they don't accept GCSE resits for that programme, ask them if this means you would not be considered if an application were submitted.
You will then have a clear answer from the source.

Okayy ty, so it rlly just depends on what each uni handle it not generic saying right?

Ultimately it is down to the uni how they implement their policies and if something is unclear, it's usually pragmatic to seek clarification from the individual unis