Silicon ioi and the Frappé environment were used to create the website. When you enter the web address, you’re taken to the site in question. A link and a button are provided to connect you to it.
If you can’t find it, add /app to the URL you’ve received. This will trigger the login screen, or if you’re already logged in, you’ll go straight to the Silicon ioi application. This mode is called “Desktop” mode.