I assume you are trying to get into medicine course in Kings college London. You require good number of A* in GCSE with good ukcat score to get considered for an interview for them. I think you are still studying at GCSE level so I advise you to gain more than 5 A* at GCSE with ukcat score more than 700 to stand a chance to get an interview but this also depends on the level of competition you get so no assurance.