XAMPP is a suit of components that will help you when you have created a web site.
When you have created your web site you put it in the htdocs folder to be able to see it using a web browser.
XAMPP is not therefore a suit of components that could possibly help or teach you how to create a web site.
You could start by learning how to install ready made web sites in to XAMPP like WordPress or Joomla, to name but a couple, as there are many available, some simple some complicated.
There are forums and installation instruction to provide you with the help you need.
There are WYSIWYG web site creation tools that may also help you get started creating a web site and Google will show you many that are available.
When you have done that, then you may be able to see how complex an issue it is creating a web site from scratch - well beyond the scope of the Apache Friends forums.
Sorry there is no easy way to become a web site designer, many of us have taken years to accumulate the knowledge and most of us are still learning new techniques - so it is an ongoing learning curve.