As you have already noticed HTML and CSS are large topics covering lot of stuff. By now you should be more comfortable breaking down a web page into its component pieces and then coding them with HTML and CSS. In addition you have the tools necessary to build your own effective visual layout.
Let’s jump right into it!
In this section you can find a lot of helpful links to other content. This is a supplemental material for you if you want to dive deeper into some concepts.
Web Fundamentals… tons of links to articles specific to your goals.
PS.. "tags" don’t really exist, they’re always technically called "elements"