https://firebase.google.com/docs/firestore/manage-data/add-data?hl=ko
import { initializeApp } from "firebase/app";
import { getFirestore } from "firebase/firestore";
const app = initializeApp(firebaseConfig);
const db = getFirestore(app);
import { collection, addDoc } from "firebase/firestore";
const onSubmit = async (event) => {
event.preventDefault();
await addDoc(collection(dbService, "nweets"), {
nweet,
createdAt: Date.now(),
});
setNweet("");
};