Answer:
You would say UN Ami that's UNE FILLE
i hope this helps i just learned it in french about five minuets ago!!!
In french the articles have gender.
Articles are the words 'a', 'an', 'the', 'this', that', 'these', 'those' etc.
So in English when you say 'a', as in a friend you do not know if you are talking about a male friend or a female friend. In french however the English article 'a' is spelled 'un' for males and 'une' for females. Therefore to say 'a friend' in french all you have to say is
either 'un ami' or 'une amie' and people (who know french) will immediately understand whether you mean a boy friend or a girl friend.