For someone that has never coded a webpage make sure you dont get sucked into the hype of HTML5 and CSS3 just yet. Although they have great features they all assume quiet a bit of knowledge of previous versions and all of the 'previews' will show you snippets related to enhanced interactivity rather than supported structural elements.
Stick to learning CSS2.1 and HTML4.01/XHTML which will give you a good grounding on which you can apply the new stuff later.
Im sure people will give this answer some negative feedback but if you need a JS snippet at the start of your code to enable the new HTML5 elements in one of the main stream browsers then it should be used for commercial purposes just yet.
