HTML stands for hyper text markup language. It is the language we all learn to design web sites.
Fortunately, Microsoft has made it quite simple to design a web site with just a working knowledge of HTML and CSS. You do not need to write your own code, so there is no memorization required of all the HTML attributes, etc.
However, you do need to know how and when to apply various tags. This means you need to become familiar with the most commonly used HTML Tags. Learn about HTML Tags.
You will find that a good working knowledge of basic HTML tags will take you a long way.