Webmaster - Create a forum on his website
Above all, a forum is usually coded in PHP (or another language for building dynamic HTML pages, ASP, JSP, etc..) Since it is about having a non-static area on its website on which visitors interact..
There are two ways to proceed:
1)Coding from scratch in PHP/ASP/ JSP ... with or without a MySQL database (or other Sybase, SQL Server, ...).
To learn PHP, here are some links:
phet(official documentation)
asp-phet
To better understand the features of MySQL, I can only advise these documents:
desqlom (official documentation)
To create a forum in the style of Kioskea's one, here is an excellent tutorial
2) Use a pre-created forum, available free online
To do this a few links, they usually explain the operation of the forum sites.
https://www.phpbbom/
It stills require a MySQL database, but once it's on your site you will have access to source code, so you can modify it to your linking.
https://punbb.informerom/
Same as PhpBB, but much lighter (in terms of design and server resources required) and, inevitabl less poweful than the latter.
https://punbb.informerom/