Are you referring to like, designing your own Web Page?
You can use some editors out there that allow for a more "graphical" approach to it (GUI), and that let you like drag on buttons and panels into different things, drag your own text boxes and like double click them to alter the height and width. I've never used one of those for web pages actually so I couldn't tell you!
BUT, you would be looking for the computer language of HTML! It's very easy and actually isn't even "programming" if I know my terminology, programming for Web is actually separate from "development" for Web! HTML has no math or anything, no strange scientific algorithms either. It's just purely made for vertically laying out your web page's "elements" as they call them or "nodes" (buttons are elements, text boxes, drop-down menus, number meters, colour wheel pickers, fly-out menus, etc.), then you use another micro/mini language called CSS (Cascading Style Sheets) to alter the horizontal positioning of your site, and also add colour and "style" in other words (there's advanced (advanced, yet unbelieveably easy) concepts like adding gradients, fancy borders, shadows on buttons or frames, etc.).
Then to do the "scripting" as they call it or "programming", you use JavaScript (JS), and if you need to do server-side programming you have a few options. You can use PHP or if you want a bit more complex approach (complex to start, but after a while it's quite intuitive if you practice) then you can use Java Enterprise Edition.
Start by downloading Notepad++, it's a type of Notepad that's downloadable and you literally just start typing your HTML code and you Save As as a .html file, or if you want to use PHP you save as a .php file (PHP code can go within an HTML page, where you add little snippets/scriptlets (I believe they are called scriptlets as well) in parts of the page and it runs just what's in that snippet within the PHP language).
PHP and JavaScript can get a bit more complex than simple graphical languages like HTML and CSS. But as for adding the "chatting" extension/widget whatever, I couldn't help you there. I know there's people that offered those old-school Shoutboxes back in the day or whatever, I'm sure you can get a chatbox plugin and you just paste it vertically where you want it in the HTML file, and it will add it I guess?
