how to add regex on html input with error message code example

Example 1: html textbox pattern mobile number

<input type="text" name="Phone Number" pattern="[7-9]{1}[0-9]{9}" 
       title="Phone number with 7-9 and remaing 9 digit with 0-9">

Example 2: name validation html

<input type="text" pattern="[a-zA-Z'-'\s]*">