System not getting upgraded in Ubuntu 20.04

Which version of virtualbox-6.1 and from which source do you have installed?

what is the output of the commands

uname -a
lsb_release -crid
dpkg -l | grep -i virtualbox
apt-cache policy virtualbox-6.1

Version 6.1.22 r144080 (Qt5.12.8) is installed.

 ---- OUTPUT of bove FOUR stuffs-----------

navin@linux:~$ uname -a
Linux linux 5.13.0-28-generic #31~20.04.1-Ubuntu SMP Wed Jan 19 14:08:10 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux
navin@linux:~$ lsb_release -crid
Distributor ID: Ubuntu
Description: Ubuntu 20.04.3 LTS
Release: 20.04
Codename: focal
navin@linux:~$ dpkg -l | grep -i virtualbox
iFR virtualbox-6.1 6.1.22-144080~Ubuntu~eoan amd64 Oracle VM VirtualBox
navin@linux:~$ apt-cache policy virtualbox-6.1
virtualbox-6.1:
  Installed: 6.1.22-144080~Ubuntu~eoan
  Candidate: 6.1.22-144080~Ubuntu~eoan
  Version table:
 *** 6.1.22-144080~Ubuntu~eoan 100
        100 /var/lib/dpkg/status
navin@linux:~$

-------END----------

The OUTPUT of above suggested commands is:
------------------------------------------------
navin@linux:~$ wget https://download.virtualbox.org/virtualbox/6.1.22/virtualbox-6.1_6.1.22-144080~Ubuntu~eoan_amd64.deb
--2022-02-10 22:37:04-- https://download.virtualbox.org/virtualbox/6.1.22/virtualbox-6.1_6.1.22-144080~Ubuntu~eoan_amd64.deb
Resolving download.virtualbox.org (download.virtualbox.org)... 49.44.204.29
Connecting to download.virtualbox.org (download.virtualbox.org)|49.44.204.29|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 89144032 (85M) [text/plain]
Saving to: ‘virtualbox-6.1_6.1.22-144080~Ubuntu~eoan_amd64.deb’

virtualbox-6.1_6.1.22-144080~Ub 100%[======================================================>] 85.01M 654KB/s in 2m 5s

2022-02-10 22:39:11 (697 KB/s) - ‘virtualbox-6.1_6.1.22-144080~Ubuntu~eoan_amd64.deb’ saved [89144032/89144032]

navin@linux:~$ sudo dpkg -i virtualbox-6.1_6.1.22-144080~Ubuntu~eoan_amd64.deb
[sudo] password for navin:
(Reading database ... 319300 files and directories currently installed.)
Preparing to unpack virtualbox-6.1_6.1.22-144080~Ubuntu~eoan_amd64.deb ...
Unpacking virtualbox-6.1 (6.1.22-144080~Ubuntu~eoan) over (6.1.22-144080~Ubuntu~eoan) ...
Setting up virtualbox-6.1 (6.1.22-144080~Ubuntu~eoan) ...
addgroup: The group `vboxusers' already exists as a system group. Exiting.

Processing triggers for systemd (245.4-4ubuntu3.15) ...
Processing triggers for gnome-menus (3.36.0-1ubuntu1) ...
Processing triggers for desktop-file-utils (0.24-1ubuntu3) ...
Processing triggers for mime-support (3.64ubuntu1) ...
Processing triggers for hicolor-icon-theme (0.17-2) ...
Processing triggers for shared-mime-info (1.15-1) ...
navin@linux:~$
-------------------------------------------------------------------

This looks good. Now try normal updates and upgrades.

THANKS.
Now it is getting normal updates and upgrades done.

Thanks Manfred Hampl, that solved my question.