You can use Firefox to create a shortcut on your computer's desktop to a page you've visited:
Resize the Firefox window so you can see both your computer's desktop and the Firefox window on the same screen.
Click the icon on the left of the address bar (where the URL is shown).
While still holding the mouse button down, move the pointer to the desktop, then release the mouse button. The shortcut will be created.
You can also drag and drop items to the desktop from the Bookmarks menu and the Library window to create shortcuts.
If you open the shortcut you made, your default browser will open, and display the page for which you made the shortcut. If you want to make Firefox your default browser, see Make Firefox your default browser.