In PHP, a variable starts with the $ sign, followed by the name of the variable:

<?php
$x = 5;
$y = "John";

echo $x;
echo "<br>";
echo $y;
?>

Add two number

<?php
// Define two numbers
$number1 = 10;
$number2 = 20;

// Add the two numbers
$sum = $number1 + $number2;

// Output the result
echo "The sum of $number1 and $number2 is $sum.";
?>