title: Fetch documents from firebase/ firestore collection
body: <p>I have a <code>'post'</code> collection in Firestore, in that post collection I have <code>'post'</code> documents.</p>
  <p>Those post documents are named as the post id. so each name is of random digits and numbers.</p>
  <p>The post documents also have quite a few fields like <code>caption</code>, <code>likes</code>, <code>UID</code>, <code>id</code>, and etc.</p>
  <p>Each post also have more collections, but I specifically want to get access to <code>&quot;post-replies&quot;</code> collection. My post replies are basically structured the exact same way as my post with an additional <code>&quot;replyingTo&quot;</code> filed.</p>
  <p>I want to fetch those replies and load them under the main post. I'm struggling to figure out fetching data on firebase, any pointers to get better would help as well.</p>