Gnome has been on the war path with Linux. And as such, you can't place icons on your desktop by default. You can try installing the icons on desktop extension to see if that allows you to do it. Some have success, while other's do not.
You can install Gnome Tweaks from the software store. Gnome Tweaks will allow you to manage your extensions. But it can also allow you to manage your appearance, as well as add system icons to the desktop!