Type in the search bar for Win10 Firefox it will show a Icon for Mozilla Firefox then right click and choose Open File Location then click on the Firefox icon and then right click then Create Short Cut then once Shortcut is made click the shortcut and then right click cut and paste to the desktop.

Please let us know if this solved your issue or if need further assistance.

Or :

Click on the URL of the page you want to create the shortcut for and then press Ctrl + C to copy. Go to your desktop, click on an empty space, then press the three bar key on your keyboard. On the context menu that will appear, choose 'New' and then on the other context menu that will appear, choose 'Shortcut'. A dialog box will appear. Paste the URL that you have copied and at the bottom click ' Continue'. You'll see the shortcut on your desktop - you can change the name to whatever you like, and you can also change the icon (if you want to).