Unable to get word by word response from GPT API

Question

I am trying to get the response from my gpt api, word by word like chatGPT generates and not all at once. I have all other things working, getting the response as expected just not in chunks .

I am able to print the partial response in console but unable to show it on UI, could anyone help here?

This is my backend code

import { ChatGPTAPI } from "chatgpt";

app.post("/", async (req, res) => {
  const { message } = req.body;
  const api = new ChatGPTAPI({
    apiKey: OPENAI_API_KEY,
  });

  const resp = await api.sendMessage(
    message, {
      onProgress: (partialResponse) => {
        console.log(partialResponse);
      },
    }
  );
  
// Code for sending the response all at once
  // if (resp.text) {
  //   res.json({
  //     message: resp.text,
  //   });
  // }
});

const server = app.listen(5000, () => {
  console.log("app listening");
});

server.headersTimeout = 610000;

This is how I am fetching it in frontend

const handleSubmit = (e) => {
    e.preventDefault();

    fetch("http://localhost:5000", {
      method: "POST",
      headers: {
        "Content-Type": "application/json",
      },
      body: JSON.stringify({ message }),
    })
      .then((res) => res.json())
      .then((data) => {
        setResponse(data.message);
        setMessage("");
      });
  };