Unable to terminate process, getting error 'access is denied'

You can try the below command using CMD

wmic process where "name='yourprocessname.exe'" delete

If this doesn't work, there are tools like

https://processhacker.sourceforge.io/index.php

https://docs.microsoft.com/en-us/sysinternals/downloads/process-explorer

Using which you can Terminate the Process.

When using Process Explorer, follow this:

• Download "Process Explorer".
• On the process properties view, select the security tab.
• Click on Permissions button.
• Click on Advanced button.
• If required, add yourself or a group you belong to.
• Edit your permissions to include "Terminate". (you will need to already have the "Change Permissions" permission or you won't be able to use it)

Sometimes, "Permissions" button can be grayed out even when you use it as "Admin", so I will recommend using above CMD command.