The best way to learn how to code is to do it manually, even if you own an HTML editor or WYSIWYG editor. Having a good sense of how to "hard code" will also help you debug pages that you build with editors.

At one time, creating web pages in a text editor was considered the best way to build websites. The precise control that handwritten code gave you over HTML was (and often still is) seen as the only way to assure quality web pages.
Professional site developers championed hand-coding because many early visual page-building programs added unnecessary code, code that affects how a page appears and how quickly it downloads over the Internet. But hand-coding is time-consuming and error-prone. One typo can render a web page useless.
Dreamweaver creates solid code even in a visual environment and since its earliest incarnation, Dreamweaver has prided itself on its ability to produce clean HTML and its tolerance for code created by other programs including text editors.
In fact, Dreamweaver includes a powerful built-in text-editing mode that lets you freely manipulate the HTML of a page, or any other code, including JavaScript, XML, PHP, and JSP. But the real story is that the code Dreamweaver produces when you work in Design mode is as solid and well-written as hand-hewn code.
Knowing this, feel free to take advantage of the increased productivity that visual-editing mode of Dreamweaver brings to your day-to-day work with its one-click objects, instant JavaScript, and simplified layout tools.
Doing so will not compromise your code and will certainly let you finish your website in record time.
Every browser interprets the HTML language slightly differently, web design is more like WYSIRWYGOAGD:

what you see is roughly what you will get, on a good day.

That is why Dreamweaver's Live View and integrated Adobe BrowserLab (a browser-testing service) can help you make sure your pages look the way you really want them to. Finally, if you have experience hand-coding HTML and CSS, you will be pleasantly surprised by Dreamweaver's powerful text-editing capabilities. In fact, even though Dreamweaver has a reputation as a visual web page editor, it is also one of the best text-editing programs on the market.