Check out example codes for "how to add telephone number in html". It will help you in understanding the concepts better.

Code Example 1

<a href="tel:5554280940">Call us at 555-428-0940</a>

Code Example 2

<label for="phone">Enter your phone number:</label>
<input type="tel" 
  id="phone" name="phone" 
  pattern="[0-9]{3}-[0-9]{2}-[0-9]{3}">

Code Example 3

<a href="tel:1234657890">Call (123)456-7890</a>

Code Example 4

Add this tag in your HTML file

<a href="tel:5554280940"></a>

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