Has anyone used Oracle VirtualBox?

From
https://www.virtualbox.org
I downloaded
virtualbox-6.1_6.1.16-140961~Ubuntu~bionic_amd64.deb

and I just double click, click on the Install Package" button.
Then open VirtualBox and I installed OpenSuse Tumbleweed, 64 bit.

So, I am able to run the OpenSuse guest OS.
I am not sure how I can transfer a file from my host (Kubuntu 18.04) to the guest OS.
The clipboard transfer does not work either.

I looked at
https://www.virtualbox.org/manual/ch...ngadditionsiso
which basically says to run
from a command prompt
sudo ./VBoxLinuxAdditions.run

and it still does not work.

This shouldn't be complicated or is it suppose to be complicated?

~~~~vmelkon