ASP.NET

[HttpPost]
       public JsonResult GetRecordById(string  id)
       {
           var record = dc.TABLE1.FirstOrDefault(x => x.PART_NO == id);
           var result = new
           {
               Name = record.PARTI,
               Type = record.TYPE
           };
           return Json(result, JsonRequestBehavior.AllowGet);
       }

<script type="text/javascript">
   $(function () {
       $("#txtParti").autocomplete({
          source: '@Url.Action("GetParti")'
       });
   });
       $(function () {
           $("#txtPtno").autocomplete({
               source: '@Url.Action("GetPtno")'
           });
       });
       $('#BTNFET').onclick(function (fetrec) {
           var recordId = this.value;
           $.post('@Url.Action("GetRecordById")',
               {
                   "id": recordId
               },
               function (data) {
                   $("#txtParti").val(data.Name);
                   $("#Type").val(data.Type);
               });
       });
   </script>

<input type="button" id="BTNFET" onclick="fetrec();" />
 @Html.EditorFor(model => model.PARTI, new { htmlAttributes = new { @class = "form-control", @id = "txtParti", @placeholder = "PART NAME" } })
@Html.EditorFor(model => model.PART_NO, new { htmlAttributes = new { @class = "form-control", @id = "txtPtno", @placeholder = "PART NO" } })
 @Html.EditorFor(model => model.TYPE, new { htmlAttributes = new { @class = "form-control", @id = "Type", @placeholder = "ITEM TYPE" } })

Can help me about to make online Shopping Website. My query is under:

1. How to add cart 
2. how to show product value in repeater (with Image) 
3. how to process billing.
4. what is way of return process  

Please suggest me my database is in linq (No SQL)  so Help me as well as earlier.

Thank You