Unable to load DLL 'db2app64.dll'

I am writing a .NET Framework application and am trying to connect to a DB2 database on a server. When trying, I get the error "System.DllNotFoundException: 'Unable to load DLL 'db2app64.dll': The specified module could not be found. (Exception from HRESULT: 0x8007007E)'". Obviously, this is because that file is not in the directory, but I am having a hard time finding out what that file is and how I get it. Here is what I currently have installed via NuGet on the project:

Anything would be helpful. Thanks.