This has been part of a lot of my projects.
The way this works: A password protected admin section allows the administrator to design the news article, complete with image(s). The article is saved to a database. The public news page is then populated from the database.
You will need a compatible scripting server such as PHP and the best companion is a MySQL database. Have a look at PHP CRUD Tutorial (part 1) to get an idea of what is involved. This is a useful widget for the creation of the article TinyMCE | The Most Advanced WYSIWYG HTML Editor
Another way is to use relevant DMXZone extensions.
Wappler is the DMXzone-made Dreamweaver replacement and includes the best of their powerful extensions, as well as much more!