Most Web pages are created using HTML - the HyperText Markup Language. You don't have to be very sophisticated in HTML to create useful Web pages. The Web contains literally hundreds of documents that can help you learn HTML:
You are also encouraged to conform to the Website Guidelines established by the Union.
These documents can give you enough knowledge to revise and extend a page you have created using the Union form. They can also enable you to read and understand the HTML representation of many Web pages, including this one, which can be seen using the "view source" capability of some browsers.
Here is an annotated list of additional documents and lists of documents about creating Web pages.