Learn Farsi: من ایمیل ندارم.

It comes from the verb "to have" (dâshtan). To make it negative, you add the negative prefix na- to the present stem -dâr-, and then add the personal ending for "I", which is -am. This gives us nadâram.

I thought the negative prefix was usually ne- (like in nemikonam). Why is it na- here?

You are right that most regular verbs use ne- for the negative present tense. However, the verb "to have" is a special exception in Farsi. It always skips the usual mi- prefix and takes the negative prefix na- instead, making nadâram, nadâri, nadârad, and so on.

The English translation says "an email", but I don't see a word for "an" in the Farsi sentence. Why?

In Farsi, when you talk about having or not having a general, nonspecific thing, you usually don't need to use the word for "a" or "an" (like yek). You just use the plain noun. So, imil nadâram literally translates to "I do not have email," which is the standard way to express this in Farsi.

Is the word imil just borrowed from English?

Yes! Farsi has borrowed several modern technology words directly from English. It is pronounced almost exactly like the English word "email", just written in the Persian alphabet.