To integrate Unzer Direct with your shop system you will need certain information that can be found in Unzer Direct Manager under Settings > Integration.
In the Shop Integration area, you will find the following information:
API user and corresponding agreement ID and API key
Payment window user and corresponding agreement ID and API key
Owner (your email address) and corresponding agreement ID and API key
You won't necessarily need all of this information, but just in case, this is where you'd go to find everything you need to integrate your shop.