Display and update MYSQL data via HTML form via PHP

$connection = mysqli_connect("localhost", "username", "password", "database_name");

$query = "SELECT * FROM table_name";
$result = mysqli_query($connection, $query);

echo "<table>";
while ($row = mysqli_fetch_array($result)) {
   echo "<tr>";
   echo "<td>" . $row['column1'] . "</td>";
   echo "<td>" . $row['column2'] . "</td>";
   // add more columns as needed
   echo "</tr>";
}
echo "</table>";

<form method="POST" action="update.php">
   <input type="text" name="column1" value="">
   <input type="text" name="column2" value="">
   <!-- add more input fields as needed -->
   <input type="submit" value="Update">
</form>

f ($_SERVER["REQUEST_METHOD"] == "POST") {
   $column1 = $_POST["column1"];
   $column2 = $_POST["column2"];
   // add more variables for additional columns
   $query = "UPDATE table_name SET column1='$column1', column2='$column2' WHERE id=1";
   mysqli_query($connection, $query);
}

mysqli_close($connection);