docs: updated example code

Author: benhalverson

apps/site/pages/en/learn/getting-started/fetch.md

@@ -8,13 +8,54 @@ authors: benhalverson, LankyMoose
 
 ## Introduction
 
-[Unidici](httpss://undici.nodejs.org) is an HTTP client libary that powers the fetch API in Node.js. It was written from scratch and does not rely on the built-in HTTP client in Node.js. It includes a number of features that make it a good choice for high-performance applications.
+[Undici](https://undici.nodejs.org) is an HTTP client libary that powers the fetch API in Node.js. It was written from scratch and does not rely on the built-in HTTP client in Node.js. It includes a number of features that make it a good choice for high-performance applications.
 
-```mjs
+## Basic GET Usage
+
+```js
 async function main() {
+  // Like the browser fetch API, the default method is GET
   const response = await fetch('https://jsonplaceholder.typicode.com/posts');
   const data = await response.json();
   console.log(data);
+  // returns something like:
+  //   {
+  //   userId: 1,
+  //   id: 1,
+  //   title: 'sunt aut facere repellat provident occaecati excepturi optio reprehenderit',
+  //   body: 'quia et suscipit\n' +
+  //     'suscipit recusandae consequuntur expedita et cum\n' +
+  //     'reprehenderit molestiae ut ut quas totam\n' +
+  //     'nostrum rerum est autem sunt rem eveniet architecto'
+  // }
+}
+
+main().catch(console.error);
+```
+
+## Basic POST Usage
+
+```js
+// Data sent from the client to the server
+const body = {
+  title: 'foo',
+  body: 'bar',
+  userId: 1,
+};
+
+async function main() {
+  const response = await fetch('https://jsonplaceholder.typicode.com/posts', {
+    method: 'POST',
+    headers: {
+      'User-Agent': 'undici-stream-example',
+      'Content-Type': 'application/json',
+    },
+    body: JSON.stringify(body),
+  });
+  const data = await response.json();
+  console.log(data);
+  // returns something like:
+  // { title: 'foo', body: 'bar', userId: 1, id: 101 }
 }
 
 main().catch(console.error);
@@ -24,15 +65,30 @@ main().catch(console.error);
 
 Undici allows you to customize the Fetch API by providing options to the `fetch` function. For example, you can set custom headers, set the request method, and set the request body. Here is an example of how you can customize the Fetch API with Undici:
 
+The [fetch](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) function takes two arguments: the URL to fetch and an options object. The options object is the [Request](https://undici.nodejs.org/#/docs/api/Dispatcher?id=parameter-requestoptions) object that you can use to customize the request. The function returns a [Promises](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_promises) that resolves to a [Response](https://undici.nodejs.org/#/docs/api/Dispatcher?id=parameter-responsedata) object. One difference between the Fetch API in the browser and the Fetch API in Node.js is that the Node.js version does not support
+
+In the following example, we are sending a POST request to the Ollama API with a JSON payload. Ollama is a cli tool that allows you to run LLM's (Large Language Models) on your local machine. You can download it [here](https://ollama.com/download)
+
+```bash
+ollama run deepseek-r1:1.5b
+```
+
+This will download the `deepseek-r1:1.5b` model and run it on your local machine.
+
 With a pool, you can reuse connections to the same server, which can improve performance. Here is an example of how you can use a pool with Undici:
 
-```mjs
+```js
 import { Pool } from 'undici';
 
 const ollamaPool = new Pool('http://localhost:11434', {
   connections: 10,
 });
 
+/**
+ * Stream the completion of a prompt using the Ollama API.
+ * @param {string} prompt - The prompt to complete.
+ * @link https://github.com/ollama/ollama/blob/main/docs/api.md
+ **/
 async function streamOllamaCompletion(prompt) {
   const { statusCode, body } = await ollamaPool.request({
     path: '/api/generate',
@@ -43,6 +99,8 @@ async function streamOllamaCompletion(prompt) {
     body: JSON.stringify({ prompt, model: 'deepseek-r1:8b' }),
   });
 
+  // You can read about hTTP status codes here: https://developer.mozilla.org/en-US/docs/Web/HTTP/Status
+  // 200 means the request was successful.
   if (statusCode !== 200) {
     throw new Error(`Ollama request failed with status ${statusCode}`);
   }
@@ -70,7 +128,9 @@ try {
 
 ## Streaming Responses with Undici
 
-```mjs
+[Streams](https://nodejs.org/docs/v22.14.0/api/stream.html#stream) is a feature in Node.js that allows you to read and write chucks of data.
+
+```js
 import { stream } from 'undici';
 import { Writable } from 'stream';