I'm not too familiar with Dreamweaver, but first you need to make sure that you have support for Chinese characters enabled in Windows. Go to Control Panel, Regional Options, Languages and install the East Asian languages files.
From then on in, you should be able to work with the Chinese text within Dreamweaver. You need to specify the charset you are going to use for the page, either GB2312 for simplified Chinese (mainland China) or Big5 for traditional Chinese (Hong Kong and Taiwan). You can also choose UTF-8 which covers all languages, and is perfect when you want to mix languages on the same page. You should be able to copy/paste in the supplied Chinese text and manipulate it as you would any other text.
It's safer to stick with GB2312 or Big5 for Chinese sites still. I'm no DW expert, but in FP I've had the most success inputting the Chinese directly into the HTML editor and skipping the WYSIWYG altogether.