Hi Muhammed,
to work with the Databus, you need to open the Data Connections on your Industrial Edge Management.
You can find it in the left menu bar as shown in the picture below
After clicking on the Databus tile, you are selecting your device on which you want the databus to configurate.
After the Launch the page is being loaded, where you can see the menu, where you can configurate everything.
Hope this answer helps you.
I am also facing the same problem after installing Databus apps on both the IEDs.
you need to install the databus configurator in the management
(OLDER VERSION) it is found in the application manager > catalog.
(Latest versions) Switch to new layout by clicking the button
Then go to applications > management and install databus configurator