udittmer wrote:JForum indeed doesn't have plugins or themes, so you would make any changes to the only available theme, which is called "default". When you run JForum, there is a top-level directory called "templates", in which you'll find the front-end code (HTML enriched with FreeMarker code to make it dynamic) and the images, JavaScript and CSS.

we would need to adapt a WYSIWYG text panel to that forum instead these one

You mean you want to use rich text editor like one of https://itsfoss.com/open-source-wysiwyg-editors/? That's possible in principle, although you'll want one that can output BBCode, since that's what JForum uses to format text. The template that contains the textarea for posts (which is where you would need to plug in the WYSIWYG editor) is called post_form.htm

So in that cas, can we take the code and try to adapt ir or it don't work in that way?

JForum is open source software, so you're free to modify it and run it with your modifications within the bounds of its license (which is quite permissive).