Check out example codes for "how to make a textbox in html". It will help you in understanding the concepts better.

Code Example 1

Simple code:
<input type="text" name="textbox_name" id="textbox_id"
class="textbox_classname">

Apart from this there are many other attributes are there which we can use in textbox
> placeholder
> style
> value 
etc..

Code Example 2

//HTML Textbox w/Getting Javascript Input:
<script>
  function getTextBox(){
    var k = document.getElemntById('myTextBox').value
    alert(k)
  }
</script>
<input type="text" id="myTextBox">
<button onclick="getTextBox()">Get Text Input</button>

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