Oui, je parle français.
Here's a breakdown of the phrase:
* Oui: Yes
* je: I
* parle: speak
* français: French
You can also say:
* Je parle français. This is a more concise way to say it, but it doesn't explicitly state that you are saying "yes."
* Oui, je suis francophone. This translates to "Yes, I am French-speaking," and is a more formal way to say it.
The best way to say it will depend on the situation and the person you are talking to.