Check out example codes for "html telephone link". It will help you in understanding the concepts better.

Code Example 1

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

Code Example 2

One click should open the phone dialler and input the number to be called.
<a href="tel:5551234567">Call (555)123-4567</a>

Code Example 3

<a href="tel:0612345678">Call me!</a>

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