How do you say what wanna talk about in french?

There are a few ways to say "what do you wanna talk about" in French, depending on the context and level of formality:

Formal:

* De quoi souhaitez-vous parler? (literally: "Of what do you wish to speak?") - This is the most formal option.

* Quel est le sujet de votre conversation? (literally: "What is the subject of your conversation?")

Informal:

* De quoi tu veux parler? (literally: "Of what do you want to speak?")

* Tu veux parler de quoi? (literally: "You want to speak of what?")

* On parle de quoi? (literally: "We speak of what?") - This is a bit more casual and can be used with friends.

You can also say:

* Qu'est-ce que tu voudrais discuter? (literally: "What would you like to discuss?")

* C'est quoi le sujet? (literally: "What is the subject?")

The best option will depend on your relationship with the person you're talking to and the context of the conversation.