If you are running the On-Premises version of Microsoft Dynamics 365 Business Central, you can install the Direct Banking apps using Windows PowerShell and the app runtime packages provided by your implementation partner.

The runtime packages are availabe on the idyn product download portal, where separate downloads are available for the different Business Central major versions:

The zip archives contain a runtime package for each Business Central minor version.
Please use the corresponding runtime package for your Business Central installation, when required in a specific localization.

To install or upgrade the Direct Banking extension, start the Business Central Administration Shell.
This will open PowerShell with the NavAdminTool module loaded.
This will allow you to use the cmdlets for installing and upgrading extensions.

If you are installing Direct Banking for the first time, please follow this guide from Microsoft.
If Direct Banking is already installed, and you want to upgrade the app to a newer version, please follow this guide from Microsoft.

For all other countries (w1) the apps from the NL folder can be used, but the NL specific apps should then be ignored.
For Ponto install the App Management App and the Direct Banking app.
For Cobase install the App Management App, the Direct Banking app and the Direct Banking Cobase.