Ha ok ...
Well, I found the following on tutorials:
Then when i go into the virtualbox menu bar, I should see a 'Device' menu which I don't. I have 'File' + 'Machine' + 'Help' so I don't know what to do.
sudo apt-get update --> ok
sudo apt-get install dkms build-essential linux-headers-`uname -r`--> apparently ok
sudo yum install dkms binutils gcc make patch libgomp glibc-headers glibc-devel kernel-headers kernel-devel --> says No package available ...
I never have a virtualbox terminal.