In French, how do you add swear words to a question?

In French, what is the equivalent of asking “What the hell is…” or “Who the f**k…” in a question? It’s been hard to find a straight answer.

For example, I was watching Inglorious Basterds, and the black Frenchman character says what sounded like “Putain… on est censé faire quoi?” which was translated in subtitles as “What the f**k are we supposed to do?”

But I was talking to a friend of mine who comes from a Francophone family (and granted, he’s from Quebec), and he didn’t understand that.

Je pense que ce pourrait utile pour améliorer ma capacité à comprendre. Merci bien!