Can I create a website puting the files directly inside the server´s folder?

At my job my boss is discussing about reworking my area website (every area of the company have it´s own website in the company intranet) and because I have some experience with HTML, CSS And JS he asked me to do it.

The website was abandoned like 8 years ago and the people that managed and designed it have left the company so nobody knows what to do and even IT doesn´t know. I only created a website at my own once in a school project with a not very good LAMP system in a raspberry pi by putting the files directly at the server´s folder without using any software like wordpress, wix, etc. It is correct if I just create the structure of folders in the server´s root and put the files inside? Is there any other requirement than creating an index.html file?

The website is very basic and it would have information about the area so there´s no need of a database, there would be just HTML, CSS, vanilla JS and PHP files; beside the images that will be shown and files that the user can download.