My Api code: 
                  <script src="../plugins/jQuery/jquery-3.5.1.min.js"></script>
                  <script type="text/javascript">
                     function hc_push() {
                     var db =''
                     var title = '"title":"'+ $('#ddl_Title option:selected').text()+'"';
                     var firstName = '"name_applicant":"'+ $("#txt_FirstName").val()+'"';
                     var gender = '"gender":"'+ $('#ddl_Gender option:selected').text()+'"';
                     var mstat = '"marital_status":"'+ $('#ddl_MaritalStat option:selected').text()+'"';              
                     var occupation = '"occupation":"'+ $('#ddl_Occupation option:selected').text()+'"';
                     var income = '"income":"'+ $('#ddl_MonthlyIncome option:selected').text()+'"';
                     var dob = '"date_of_birth":"'+ $("#txt_dob").val()+'"';
                     var addr1 = '"address1":"'+ $("#txt_AddressLine1").val()+'"';
                     var addr2  = '"address2":"'+ $("#txt_AddressLine2").val()+'"';
                     var pin    = '"pin_code":"'+ $("#txt_pincode").val()+'"';
                     var state  = '"state":"'+ $('#ddl_state option:selected').text()+'"';
                     var dist   = '"district":"'+ $('#ddl_district option:selected').text()+'"';
                     var mobph  = '"mobile":"'+ $("#txt_MobphoneNo").val()+'"';
                     var ecode  = '"introducer_emp_code":"'+ $("#txt_IntrEmpCode").val()+'"';
                     var ename  = '"emp_name":"'+ $("#txt_IntrEmpName").val()+'"';
                     var brcode = '"branch_code":"'+'BEL'+ $('#ddl_BranchList option:selected').text()+'"';
                     var brtype = '"branch_type":"'+'BEL'+'"';
                     var custid = '"crmbel_customerid":"'+ $("#txt_CustomerID").val()+'"';
                     var leadid = '"crmbel_lead_id":"'+'78996'+'"';
                     var stat   = '"status":"'+'0'+'"';
                     var txnmod = '"transaction_module":"'+'399'+'"';
                     var nomname = '"nom_name":"'+ $("#txt_NomineeName").val()+'"';
                     var nomrltn = '"nom_relation":"'+ $('#ddl_NomineeRelation option:selected').text()+'"';
                     var nomage = '"nom_age":"'+ $("#Txt_NomineeAge").val()+'"';
                     var profname = '"proof_name":"'+ $('#ddl_dob_proof option:selected').text()+'"';
                     db = title+','+firstName+','+gender+','+mstat+','+occupation+','+income+','+dob+','+addr1+','+addr2+','+pin+','+state+','+dist+','+mobph+','+ecode+','+ename+','+brcode+','+brtype+','+custid+','+leadid+','+stat+','+txnmod+','+nomname+','+nomrltn+','+nomage+','+profname
                     //alert(db); 
                        
                        $.ajax({
                        type: "POST",
                        url: "http://test.xyz.com:83/xyz_webservice/xyzpush_api.php",
                        data: '{' + db + '}',
                        contentType: "application/json; charset=utf-8",
                        dataType: "json",
                        success: function (response) {
                        debugger;
                        var result = response.d;
                        if (result == '100') {
                        alert("Success!");
                        }
                        else if (result == '111') {
                        alert("Sorry!");
                        }
                        else if (result == '116') {
                        alert("Invi.Customer_id!");
                        }
                        else {
                        alert("Sorry! There is an err. on Data Transmission, please contact IT Admin!");
                        }
                    },
                    error: function (ex) {
                        alert("Sorry there is an err. Ex: " + ex);
                    }
                    
                });
                }
        </script>
    

As per the Partners API Document, hereby I mentioned sample input Parameters:

    {"title":"Mr","name_applicant":"Marav","gender":"Male","marital_status":"Unmarried","occu
    pation":"TEACHER","income":"45000","date_of_birth":"01-07-1982","address1":"Address 
    1","address2":"Address 
    2","pin_code":"560075","state":"City","district":"KARNATAKA","mobile":"7795471996","int
    roducer_emp_code":"MF39349","emp_name":"PRASHANTH H 
    S","branch_code":"BEL12","branch_type":"BEL","crmbel_customerid":"553399877","crmbel
    _lead_id":"78996","status":"0","transaction_module":"399","nom_name":"sam","nom_relatio
    n":"spouse","nom_age":"34","proof_name":"DOB"}


Here I have mentioned Partners Output Parameters

    ESPONSE 1:
    {"code":"100","result":"success","api_response_message":"Successfully 
    Inserted","customer_id":"553399877"}
    RESPONSE 2:
    {"code":"111","result":"error","api_response_message":"Duplicate 
    Entry","customer_id":"553399877"}
    RESPONSE 3:
    {"code":"113","result":"error","api_response_message":"Branch code does not exist or crm 
    status not 
    enabled","customer_id":"","mstl_response1":"","mstl_response2":"","mstl_response3":""}
    RESPONSE 4:
    {"code":"114","result":"error","api_response_message":"district,nom_name,nom_relation,no
    m_age,introducer_emp_code,Uploaded proof name,Proof file : value cannot be 
    null","customer_id":"","mstl_response1":"","mstl_response2":"","mstl_response3":""}
    RESPONSE 5:
    {"code":"116","result":"error","api_response_message":"Invalid Data","customer_id":""}