GeoGebra allows you to create interactive webpages, so called Dynamic Worksheets, from your files. In the File Menu, you need to select item Export, then click on item Dynamic Worksheet as Webpage (html). This opens the export dialog window for Dynamic Worksheets.
Under this tab you can enter a titel for your construction, a text above and below the construction (e. g. a description of the construction and some tasks), and then Upload it to GeoGebra.
If you want to create an html file on your computer, see Export as html Webpage for details.