Parent Page Redirect to Child Page without Code

Hi,

I was wondering how to redirect a parent page to the first child page without using code, as I have only just started working with Word Press.

I came across a forum that worked it out using code but i don’t understand where to put it or anything.

The code was:

1) Create a new template file and paste the following code into it:

<?php
/*
Template Name: Redirect To First Child
*/
if (have_posts()) {
while (have_posts()) {
the_post();
$pagekids = get_pages(“child_of=”.$post->ID.”&sort_column=menu_order”);
$firstchild = $pagekids[0];
wp_redirect(get_permalink($firstchild->ID));
}
}
?>

2) save and upload your new template into your theme directory.

3) Edit your Parent page and apply the “Page Template”.

Note: adding the page template is located down towards the bottom of the page.

my website is https://www.dkyogacentre.com and Im trying to make the Services page go directly to the Yoga Classes page.

If anyone could help that would be great.

Thanks