Getting "DebugType" parameter is not supported by the "XamlCTask" task error on building my Xamarin ios project

I had the same error but with xamarin Debugging on an android device. I would recommend that you check your Nuget packages? I had different versions of Xamarin.Forms which caused conflicts. Obviously you need to make sure that they are all on equal versions of forms.

Check and Consolidate your Xamarin Nuget packages to the latest stable version.

Open the .csproj in a text editor. Then remove,

<Error Condition="!Exists(...

within,

<Target> Name="EnsureNuGetPackageBuildImports" BeforeTargets="PrepareForBuild">    
    //
    <Error Condition="!Exists('...
    //
</Target>

that is related to raising this error.

Then rebuild the project, it should work.