Can I connect to json file manually from the code on WPF App for example?

[HusHam1414]

I'm trying to use the plugin on WPF App
I install it from NuGet and it looks like working fine
but the problem is in the setup and connect to JSON file

is there any way to connect to the JSON file manually from the code, I already search for this but I can't find any method

var items = await CrossCloudFirestore.Current .Instance .GetCollection("Items") .WhereEqualsTo("Deleted", false) .OrderBy("AddDate", true) .GetDocumentsAsync();

this error appears when I try to use the code:

System.NotImplementedException: 'This functionality is not implemented in the portable version of this assembly. You should reference the NuGet package from your main application project in order to reference the platform-specific implementation.'