If that's the case (HbA1c of 6.5%) then it's equivalent to 47.6, which is just under the normally assumed diabetic threshold of 48. But if the nurse said 'anything under 70 (7.0%, 53 mmol/mol) is OK, that's wrong for a diagnosis.
Either way you are in a reasonable place to start managing the condition and get back to non-diabetic levels. The key to this is to reduce carbs as well as obvious sugars, and the advice given on the other thread still holds. The nurse's advice to 'eat healthily' almost certainly refers to the NHS 'Eatwell Plate' which is disastrous for most diabetics as it contains far too many carbs.
Good luck, read around more and ask any questions.