What is the conclusion to Me Talk Pretty One Day?

Both the title essay and the collection of essays refer to the deep, complex connections between language and identity.
David Sedaris learned a second language as an adult as part of his developing relationship with Hugh, who was the one who wanted to move to France. Moving overseas with him was an important part of committing not only to another man but to his identity as an adult gay man. Ironically, this aspect of adulthood was accompanied by the infantilizing experience of attending language classes. And as part of the process of building a home with Hugh and feeling at home in Paris, he spent large amounts of time with fellow strangers or "refugees" in the class.
The conclusion that Sedaris comes to is both about learning language and acquiring self-knowledge more generally. Understanding who you are rarely comes as an epiphany—it is incremental, and the realization sneaks up on you.

Understanding doesn’t mean that you can suddenly speak the language. Far from it. It’s a small step, nothing more, yet its rewards are intoxicating and deceptive.

Me Talk Pretty One Day is the title of a series of essays by David Sedaris, but it's also the title of the eponymous essay, which doesn't come last in the book. Thus, the answer depends on whether you're referring to the essay itself or to the entire book.
The essay "Me Talk Pretty One Day" is about Sedaris learning French while living in Paris. He talks about going back to language school and meeting the other students in the class, who are all from different countries. The teacher is a sneaky and bitter woman who mocks the students. He has trouble grasping the language and feels like he won't be able to get alone with any fluency.
One day, the teacher tells him that "every day spent with you is like having a cesarean section." He understands her; Sedaris notes that it's his first full French sentence where he's understood every word. She insults him again and he happily tells her that he understands her and asks her to "talk me more, you, plus, please, plus."
The book Me Talk Pretty One Day ends with an essay titled "I'll Eat What He's Wearing." It's a story about his father visiting Sedaris and his partner Hugh in France. It paints a picture of his father as a thrifty man who eats old, rotten food and buys at a discount whenever he can. He recalls biting into produce in his childhood home and instead of feeling the crunch of it between his teeth, feeling it softly give way.
The story ends with his father explaining that he found something brown in his suitcase, started to eat it, and then realized it was a piece of a hat that had fallen off. Sedaris says to the reader that it may seem his father stopped eating because it wasn't food—but that wasn't the case. He says his father stopped eating to save it for later since now, having not killed him, he knew the cap was edible.