I assume you mean file and folder icons on the Desktop and not the disk icons.
If so, what you could do is open a Finder window to
<user home folder>/Desktop/
If those files and folder are still on your Desktop but somehow off the screen, they should show up there in the Finder window showing your Desktop folder.
If they can be seen there, move them to a new location, such as a new folder in your Documents folder. Then, move them from there back onto your Desktop.
If by chance your missing the Dock (the row of icons along the bottom of the screen) you can use either the ⌥⌘D (alt command D) key combination or click the Apple on the menu bar and move the cursor down to Dock and Turn Hiding On/Off .