You can withdraw from your remaining exams, but you will still get a grade (probably a U as you haven't completed all the assessments I would guess) and you will still need to declare this when you apply through UCAS. Whether universities have an issue with that or not probably depends on the university and course in question, although retaking an exam and getting a lower result (or a U in this case from not completing all the exams) might be a bit of a red flag.
You can see if you can apply for mitigating/extenuating circumstances with the exam board. Barring that you could just not take the remaining exams this year, then retake them all fresh next year where you're hopefully in a better situation.