How to activate CPU driver in Ubuntu 20.04

I am new to Linux. I installed Ubuntu on VirtualBox. I have install cpufreqtils by command :

trinh@TrinhHuy:~$ sudo apt install cpufreqtils

Then I check the information of CPU.Here the output:

trinh@TrinhHuy:~$ cpufreq-info
cpufrequtils 008: cpufreq-info (C) Dominik Brodowski 2004-2009
Report errors and bugs to [email protected], please.
analyzing CPU 0:
  no or unknown cpufreq driver is active on this CPU
  maximum transition latency: 4294.55 ms.
analyzing CPU 1:
  no or unknown cpufreq driver is active on this CPU
  maximum transition latency: 4294.55 ms.
analyzing CPU 2:
  no or unknown cpufreq driver is active on this CPU
  maximum transition latency: 4294.55 ms.
analyzing CPU 3:
  no or unknown cpufreq driver is active on this CPU
  maximum transition latency: 4294.55 ms.

I also check the recommend driver for the system

trinh@TrinhHuy:~$ ubuntu-drivers devices
== /sys/devices/pci0000:00/0000:00:04.0 ==
modalias : pci:v000080EEd0000CAFEsv00000000sd00000000bc08sc80i00
vendor   : InnoTek Systemberatung GmbH
model    : VirtualBox Guest Service
manual_install: True
driver   : virtualbox-guest-dkms - distro non-free
driver   : virtualbox-guest-dkms-hwe - distro non-free

== /sys/devices/pci0000:00/0000:00:02.0 ==
modalias : pci:v000015ADd00000405sv000015ADsd00000405bc03sc00i00
vendor   : VMware
model    : SVGA II Adapter
driver   : open-vm-tools-desktop - third-party free

How can I activate the CPU driver OR the VirtualBox already provide me with CPU stimulation model : VirtualBox Guest Service? Please help !

Thanks for reading.