select the specified checkbox as selected in radio button and remove the attribute as disabled

$("#custWorkType").removeAttr("disabled");



$('input:radio[name=in_invoicetype]')[2].checked = true;

Get selected radio button value using jquery

if ($("input[name=in_invoicetype]:checked").val() == "Custom") {
   
                  alert("workTypeval====>" + $("input[name=in_invoicetype]:checked").val());
   
      }