I'm not going to bore everyone with the basics too much, because an experienced web developer will have those down. The basics include the code to start HTML and stop HTML as well as headings, paragraphs, and so forth.
There are two tags that tell the browser you've got an html document whether you are saving the file as php, htm, html, asp, or the many other formats that HTML can have. They are the HTML tag and the body tag. In the begining of the HTML tag, you have a head tag, title tag, and any script that needs to be here within this tag for them to run. There is an opening tag for these, and a closing tag for these as well. The following is an edit box you can use to review the code for this web site as is.As you can see, the body tag has many elements for color, links, visited links, and so forth. The head and title tag just include my site's name and what page you're on. I could put other tags before the closing head tag as needed, and then close that head tag. There is nothing special about the beginning of HTML, just knowing that this is how your web page is laid out. The web browser renders this code above and displays my web page as is.
Within the body tags, you will see the text. We can put paragraph tags which is a p tag within the less-than and greater-than signs, and the same but the slash to close although it isn't necessary. Here is the same textarea, with the first paragraph to show you how this is done.
You can put headings which are h followed by a number within the same type of code, and even put forms and more within this same thing. The web browser treats this whole thing as a web page in which you are able to navigate. Links are used as well. Since this is dealing with accessibility issues I've found, I'm not going to cover more basics, but this can give you a hand in finding a little bit of help to get started. Paragraphs, headings, and links are all accessible by default, so there are really no reasons to continue from this point.
You may choose from the following links to continue.