I am new to using Ubuntu. I am trying to install PEAK CAN driver so I can see the CAN messages in LINUX environment using VirtualBox. But it seems as if I need to sign a pcan kernal module… and I really am not sure how to do it. This is the error message I get after running

@jerinj89-VirtualBox:~$ sudo modprobe pcan
@jerinj89-VirtualBox:~$ dmesg | grep pcan
[  149.692697] pcan: loading out-of-tree module taints kernel.
[  149.692709] pcan: module verification failed: signature and/or required key missing -   tainting kernel
[  149.697596] pcan: Release_20240521_n (le)
[  149.697599] pcan: driver config [mod] [isa] [pci] [pec] [usb] 
[  149.697793] usbcore: registered new interface driver pcan
[  149.697797] pcan: major 240.

I need to resolve the below error
pcan: module verification failed: signature and/or required key missing – tainting kernel

I have tried googling this, and followed the steps from https://ubuntu.com/blog/how-to-sign-things-for-secure-boot/

but again got an error EFI variables are not supported on this system for command sudo mokutil –import MOK.der

I cannot find a clear and concise answer with sequential steps. Again, I am fairly new to linux, so any help is welcome. Thanks in advance.