On ubuntu 16.04 (100% satisfaction) I used to select and open folders/files on desktop using keyboard, up/down, left/right arrow keys; not the mouse. I cannot do this anymore on ubuntu 20.04 Any work around ?
Desktop icons are now provided by a Gnome Shell extension, which is still very new and underdevelopped.
A workaround is to navigate your icons in the file manager: they live in the "Desktop" folder.
If an active desktop is critical in your workflow, you better move to a desktop environment that fully supports them: Xubuntu, Kubuntu, ... Ubuntu uses Gnome Shell. Gnome Shell does not support an active desktop at all. Ubuntu wants to support it, but has to resort to a half ready Gnome Shell extension to do so, because the file manager Files (nautilus) does not anymore support this.
A rather technical option would be to move to the nemo or caja file managers, so these can manage the desktop.