About this site

This site has been made ONLY using HTML, PHP, CSS and JS. I will not write strictly about HTML construction, there are many tutorials on the Internet. But the subpage system ... it was something different. I searched for three hours and couldn't find anything helpful. Each subpage is an .php file with the following content:
< ?php @ require_once "../menu.html" ? >
content of the div
< ?php @ require_once "../footer.html" ? >
menu.html and footer.html contain only the structure of the page. If someone wants to make such a site, I really recommend the course of Miroslaw Zelent. For now I have to work out a way to force .htaccess to work. Everything in this topic.