vboxdrv kernel module is not loaded..[redhat 8]

I had followed all of them:

• https://www.if-not-true-then-false.com/2010/install-virtualbox-with-yum-on-fedora-centos-red-hat-rhel/

• https://www.binarytides.com/fix-vbox-kernel-driver-error/

At the time I am trying to run VirtualBox I am getting the warning:

WARNING: The vboxdrv kernel module is not loaded. Either there is no module
         available for the current kernel (4.18.0-147.0.3.el8_1.x86_64) or it failed to
         load. Please recompile the kernel module and install it by

           sudo /sbin/vboxconfig

         You will not be able to start VMs until this problem is fixed.

and on running with

sudo modprobe vboxdrv

I am getting:

modprobe: ERROR: could not insert 'vboxdrv': Required key not available

Can someone help me with this?