It appears that "Homie" is an application window - perhaps blank because the app has not been setup.
You should be able to close that window by clicking the title and then click the red 'close' button in the top left corner of the window.
You should also be able to 'Quit' the Homie application just like any other.
As @Owl-53 has indicated, you can check to see if the app is configured to load at startup. If it is on the list at System Settings > General > Login Items & Extensions, you may remove it from that list.
If this is something you don't recall downloading, and likely aren't using, feel free to delete the app from the Applications folder. If you decide later that it's something you might like to use, download it again from the App Store.