docs: rephrasing for understanding (#2783)

* docs: rephrasing for understanding

* docs: rephrasing component basics

* docs: rephrased for better understanding

* docs: added comment to code

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Co-authored-by: 404answernotfound <[email protected]>

src/guide/essentials/component-basics.md

@@ -469,6 +469,7 @@ Something bad happened.
 This can be achieved using Vue's custom `<slot>` element:
 
 ```vue{4}
+<!-- AlertBox.vue -->
 <template>
  <div class="alert-box">
  <strong>This is an Error for Demo Purposes</strong>