How to read Json object from C# app settings

I have a kubernetes configuration in json format file which i want to deployed in kubernetes cluster using C# kubernetes clinet api.Below is my config data file.But i want to read this values from appsettings.json. Values is always null when i tried to read this from appsetting.json using Microsoft.Extensions.Configuration .Below is yaml file

{
"yaml":{
    "apiVersion": "batch/v1beta1",
    "kind": "CronJob",
    "metadata": {
        "creationTimestamp": "2020-08-04T06:29:19Z",
        "name": "esignature-cron",
        "namespace": "esignature"
    },
    "spec": {
        "concurrencyPolicy": "Forbid",
        "failedJobsHistoryLimit": 1,
        "jobTemplate": {
            "metadata": {
                "creationTimestamp": null
            },
            "spec": {
                "template": {
                    "metadata": {
                        "creationTimestamp": null,
                        "labels": {
                            "app": "your-periodic-batch-job"
                        }
                    },
                  "spec": {
                        "containers": [
                            {
                                "image": "pystore.azurecr.io/py-app1:1.0.0",
                                "imagePullPolicy": "IfNotPresent",
                                "name": "redmine-cron",
                                "resources": {},
                                "terminationMessagePath": "/dev/termination-log",
                                "terminationMessagePolicy": "File"
                            }
                        ],
                        "dnsPolicy": "ClusterFirst",
                        "imagePullSecrets": [
                            {
                                "name": "dockerpull"
                            }
                        ],
                        "restartPolicy": "OnFailure",
                        "schedulerName": "default-scheduler",
                        "securityContext": {},
                        "terminationGracePeriodSeconds": 30
                    }
                }
            }
        },
        "schedule": "*/1 * * * *",
        "successfulJobsHistoryLimit": 3,
        "suspend": false
    }
}
"ConnectionString":"test"
}

C# code

using Microsoft.Extensions.Configuration;
namespace yamlread.Services.Implementation
{
public class yamlread : Iyamlread
    {
 public IConfiguration Configuration { get; }
 public string yaml { get; set;}
 public yamlread( IConfiguration config)
 {
     Configuration =config;
     yaml=Configuration["yaml"]
 }