In German 'Freund' is male friend and 'Freundin' is female friend. The '-in' suffix is used for female professions as well e.g. 'Professorin'.
If you mean that you can't tell the difference between Freundin meaning girlfriend or friend, you're right you can't tell just from the one sentence. You need more information because the word can mean both. A way to get round this is to say 'eine Freundin von mir' which means 'a friend of mine' if you're not talking about your girlfriend.
And if you just want to translate the English word 'friend' into German, you have to know from the context whether they're male or female, because 'Freund' doesn't work for both male and female - it means a male friend.
Hope that answered your question.