These instructions are for Windows Laptops/Desktops
XAMPP can work on MacBook, but you're better off configuring each piece separately (Apache Web Server, MariaDB, PHP, etc)
MacBook ships with the Apache Web Server pre-installed and configured - so XAMPP installs in an obscure location to avoid the conflict
XAMPP installs to c:/xampp and creates a heirachy of folders
Check to make sure the folder c:/xampp/htdocs exists. This is going to be our working directly.
htdocsweb-assets web-assets/tpl web-assets/lib
css and js folders into c:/xampp/htdocs/web-assets/c:/xampp/htdocs/web-assets/js/jquery-3.4.1.min.jsc:/xampp/htdocs/web-assets/css/site.cssc:/xampp/htdocs/web-assets/tpl/app_header.phpc:/xampp/htdocs/web-assets/tpl/app_footer.phphtdocs <--- this is your ['DOCUMENT_ROOT']
`-- web-assets
|-- css
| |-- bootstrap-grid.css
| |-- bootstrap-grid.css.map
| |-- bootstrap-grid.min.css
| |-- bootstrap-grid.min.css.map
| |-- bootstrap-reboot.css
| |-- bootstrap-reboot.css.map
| |-- bootstrap-reboot.min.css
| |-- bootstrap-reboot.min.css.map
| |-- bootstrap.css
| |-- bootstrap.css.map
| |-- bootstrap.min.css
| `-- bootstrap.min.css.map
|-- js
| |-- bootstrap.bundle.js
| |-- bootstrap.bundle.js.map
| |-- bootstrap.bundle.min.js
| |-- bootstrap.bundle.min.js.map
| |-- bootstrap.js
| |-- bootstrap.js.map
| |-- bootstrap.min.js
| |-- bootstrap.min.js.map
| `-- jquery-3.4.1.min.js
|-- lib
`-- tpl
|-- app_footer.php
`-- app_header.php
myfirstpage.php) using the following starter template:
<?php
$page_title = "My First Bootstrap Page";
include_once $_SERVER['DOCUMENT_ROOT'] . '/web-assets/tpl/app_header.php';
echo "<h1>Hello World!</h1>";
include_once $_SERVER['DOCUMENT_ROOT'] . '/web-assets/tpl/app_footer.php';
?>
http://localhost/myfirstpage.php and should look like this