how to enter to new line in php code example

Example 1: new line php

<?php
echo "If you view the page source \r\n you will find a newline in this string.";
echo "<br>";
echo nl2br("You will find the \n newlines in this string \r\n on the browser window.");
?>
  // 2 Way
  <?php echo $clientid, ' ', $lastname, PHP_EOL;?>

Example 2: php new line

//let a variable contain multiple line
//add <br> tag in string
$variable = "123 <br> ";