How to verify if VT-x or AMD-V is activated without rebooting in BIOS
I must be a lucky fellow, :) I have found this program. Open up the terminal(CTRL+Alt+t)
sudo apt-get update
sudo apt-get install cpu-checker
Then enter the command below
sudo kvm-ok
If you receive this output
INFO: /dev/kvm exists
KVM acceleration can be used
All is good. If you don't receive this output, you have to enter the BIOS/UEFI and to enable virtualization.
systemctl --firmware-setup reboot
The settings can look different from system to system due to the BIOS/UEFI OEM's like. Some examples
With this command you can verify if your CPU is even capable, which most CPU's nowadays are.
grep -E 'svm|vmx' /proc/cpuinfo
With this command you can ensure if the proper kernel module is loaded after. The BIOS settings had been enabled
# lsmod | grep kvm
Further reading
https://www.thomas-krenn.com/en/wiki/Activating_the_Intel_VT_Virtualization_Feature
These articles have been archived, the original links are dead :(
https://www.smarthomebeginner.com/enable-hardware-virtualization-vt-x-amd-v/
Some info in German