ASP.Net: Load data from JSON to Generic Collection in C# and VB.Net

dear all,

this is my class

public class Document
{
    public int id { get; set; }
    public int categoryId { get; set; }
    public string referenceNumber { get; set; }
    public int referenceSequence { get; set; }
    public int sendingEntityId { get; set; }
    public int statusId { get; set; }
    public int priorityId { get; set; }
    public int privacyId { get; set; }
    public int privacyLevel { get; set; }
    public string subject { get; set; }
    public int documentTypeId { get; set; }
    public DateTime dueDate { get; set; }
    public int attachmentId { get; set; }
    public DateTime createdDate { get; set; }
    public DateTime modifiedDate { get; set; }
    public int createdByUserId { get; set; }
    public int createdByStructureId { get; set; }
    public bool isLocked { get; set; }
    public List<Transfer> transfers { get; set; }
    public List<int> documentReceiverEntity { get; set; }
    public Form form { get; set; }
    public DateTime initialCreatedDate { get; set; }
    public string ocrContent { get; set; }
    public string body { get; set; }
    public List<object> keyword { get; set; }
}
public class Form
{
    public string OldStatus { get; set; }
    public string OldDocTransferStatus { get; set; }
}
public class Transfer
{
    public int id { get; set; }
    public int documentId { get; set; }
    public int statusId { get; set; }
    public int fromStructureId { get; set; }
    public int fromUserId { get; set; }
    public int toStructureId { get; set; }
    public int toUserId { get; set; }
    public DateTime openedDate { get; set; }
    public int ownerUserId { get; set; }
    public DateTime closedDate { get; set; }
    public DateTime dueDate { get; set; }
    public DateTime createdDate { get; set; }
    public int createdByUserId { get; set; }
    public bool cced { get; set; }
    public string instruction { get; set; }
    public int? purposeId { get; set; }
    public int? parentTransferId { get; set; }
}

I want to load the data from the datatable with model to post bulk data as json. I created the model class as below but for transfer list i'm unable to add

var doc = new Document()
{
    id = 1223,
    categoryId = model.categoryId,
    referenceNumber = model.referenceNumber,
    referenceSequence = model.referenceSequence,
    sendingEntityId = model.sendingEntityId,
    statusId = model.statusId,
    priorityId = model.priorityId,
    privacyId = model.privacyId,
    privacyLevel = model.privacyLevel,
    subject = model.subject,
    documentTypeId = model.documentTypeId,
    dueDate = model.dueDate,
    attachmentId = model.attachmentId,
    createdDate = model.createdDate,
    modifiedDate = model.modifiedDate,
    createdByUserId = model.createdByUserId,
    createdByStructureId = model.createdByStructureId,
    isLocked = model.isLocked
     
    //adding transfers list
};

Sample Data:

{
  "id": 1,
  "categoryId": 1,
  "referenceNumber": "1",
  "referenceSequence": 1,
  "sendingEntityId": 1,
  "statusId": 1,
  "priorityId": 1,
  "privacyId": 1,
  "privacyLevel": 1,
  "subject": "subject",
  "documentTypeId": 1,
  "dueDate": "2017-08-02T00:00:00",
  "attachmentId": 138814,
  "createdDate": "2017-06-20T00:00:00",
  "modifiedDate": "2023-11-07T21:52:05.7729550",
  "createdByUserId": 1,
  "createdByStructureId": 1,
  "isLocked": false,
  "transfers": [
    {
      "id": 1,
      "documentId": 1,
      "statusId": 1,
      "fromStructureId": 1,
      "fromUserId": 1,
      "toStructureId": 1,
      "toUserId": 1,
      "openedDate": "2017-06-21T14:17:21.3433333",
      "ownerUserId": 1,
      "closedDate": "2017-06-21T15:14:18.4966667",
      "dueDate": "2017-08-02T00:00:00",
      "createdDate": "2017-06-21T14:17:21.3433333",
      "createdByUserId": 1,
      "cced": false,
      "instruction": ""
    },
    {
      "id": 2,
      "documentId": 2,
      "statusId": 2,
      "purposeId": 2,
      "fromStructureId": 2,
      "fromUserId": 2,
      "toStructureId": 2,
      "toUserId": 2,
      "openedDate": "2017-06-21T15:14:18.4500000",
      "ownerUserId": 2,
      "closedDate": "2017-06-21T19:26:15.5366667",
      "dueDate": "2017-08-02T00:00:00",
      "parentTransferId": 2,
      "createdDate": "2017-06-21T15:14:18.4500000",
      "createdByUserId": 2,
      "cced": false,
      "instruction": ""
    }
     
  ],
  "documentReceiverEntity": [
    19554
  ],
  "form": {
    "OldStatus": "Completed",
    "OldDocTransferStatus": "1"
  },
  "initialCreatedDate": "2017-06-21T14:15:45.6900000",
  "ocrContent": "",
  "body": "",
  "keyword": []
}

I want to send the data as sample data from the datatable.

Thank you very much