there are tons of free online tutorials. Start with html obviously and I would also recommend learning CSS after html. Then move on to javascript, then php.
html you will learn mostly layout
CSS you will learn more layout and styling the layout
AND be sure to learn HTML 5, not previous versions
here is one link to get you started.
http://blog.templatemonster.com/2010/06/16/25-html5-tutorials-techniques/
