Hi Jane,
The important bit is to have your testing-server set up and working, and then the rest is fairly straight forward.
You say you have found support to set up the testing-server, so just for your info it might be useful to cast an eye over a start-to-finish example of what needs to be done to start creating a dynamic site in DreamWeaver. I wrote a reply to someone else Here which may (or may not) be useful to you.
To make a static (html) page dynamic (php, if you're using WebAssist extensions) you just give your page the .php extension - rather than .htm or .html . This simply lets the server/browser know how to process the pages. You can save an existing html page - say index.html - as index.php and it becomes a dynamic page, ready for use with WebAssist's extensions. New pages you would create by Dreamweaver Menu > File > New > Blank Page > PHP.
Once you have your testing-server up and running you will be able to preview the results as if the site were on a remote php enabled server. An easy, fully featured solution is to download XAMPP - this comes with mySql (and phpMyAdmin to administrate it with) and is easy to set-up.