Click to call is a great option for mobile devices to add Click to call button. Once Added a user can tap the phone and make a call directly from your website.
Most modern browsers support this function.Follow instructions below to add it.
Here is syntax:
Tap on Phone Number to Call <a href="tel:+91-801-064-3980"> +91 (801) 064-3980 </a>
It is best practice to add phone numbers in international format.