To use Bandizip on the Finder's right-click menu, you should configure the system to use the Finder extension of Bandizip. You may find that, however, if and when you enable the Finder extension of Bandizip, the Finder displays icons external volumes incorrectly in the sidebar.
This issue occurs by macOS itself and is reported not only with Bandizip but also with many other apps utilizing the Finder extension. Currently, third-party app developers cannot fix the issue and it is believed that actions from Apple are required.
If you do not want the icon displayed incorrectly, for now, you should disable "Enable the Finder menu on external drives" in the preferences of Bandizip or disable the Finder extension of Bandizip.