So with the "fare" construction, the use of the definite article is because the occupation is represented as a type/category (like in English "The computer has revolutionized..." where it's not a particular/definite computer, but rather "the computer" as an abstract class)? And for "essere," the occupation doesn't need to be represented that way?
Rather, when you use the forms of "essere" you can translate word by word from English; the Italian idiom "fare il/lo/la X" literally translates to "do the X" (not be) and means something closer to "play the X", i.e. perform what's required of the role X. It also works with non-professions, e.g. "fare lo scemo" (act like a fool) or "fare il furbo" (be crafty/underhanded). The subtle difference becomes evident when you say e.g. "sono uno scrittore ma faccio il barista per mantenermi" (I'm a writer but I work as a barman to support myself): the first is what you are, i.e. the profession you associate with, the second is what you do, i.e. the profession you are performing.
Conducente is used for car drivers and sometime even for bus driver. Conduttore is not very used. Anyways, actually "autista" is the right translation of driver
You can use those interchangeably; autista is more informal, conducente sounds more like a word the news would use.
My (proper paid-for bound) dictionary has Direttore for a musical conductor, Bigliettaio for a bus conductor, Controllore for a conductor in the US train sense, and Conduttore for an electrical conductor (i.e. thing, not person) - which would be a strange thing to say about your uncle, even if strictly he is one. And Autista for a bus driver or chauffeur. Conducente for driver of a car. But I am not a native Italian speaker.
In your case you can say that:
- My uncle is the presenter (of this show) = Mio zio è il conduttore (di questa programma)
But Duo means just an occupation. In Italian there are three ways to say "My uncle is a presenter" or "My uncle works as a presenter":
- Mio zio fa il conduttore
- Mio zio è un conduttore
- Mio zio lavore come conduttore
In italian "fa" is used to indicate someone's actions or Job. Both "è" or "fa" are corrects, but the first form denotes a more passive sense of the phrase, while the second a more active sense. But is perfectly correct say: "Mio zio fa l'idraulico" ---> "My uncle is a plumber" "Mio zio è un idraulico" ---> "My uncle is a plumber" They mean the same thing. Hope I've been clear ^^