Hi tripurarijha1...,

Refer below sample code.

HTML

<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
<script type="text/javascript" src="https://www.gstatic.com/charts/loader.js"></script>
<script type="text/javascript">
    google.charts.load('current', { 'packages': ['corechart'] });
    google.charts.setOnLoadCallback(drawChart);
    function drawChart() {
        var options = {
            title: 'USA City Distribution'
        };
        var chartType = $("#rblChartType input:checked").val();

        //3D Pie Chart
        if (chartType == "2") {
            options.is3D = true;
        }

        //Doughnut Chart
        if (chartType == "3") {
            options.pieHole = 0.5;
        }
        $.ajax({
            type: "POST",
            url: "Default.aspx/GetChartData",
            data: '{}',
            contentType: "application/json; charset=utf-8",
            dataType: "json",
            success: function (r) {
                var data = google.visualization.arrayToDataTable(r.d);
                var chart = new google.visualization.PieChart($("#chart")[0]);
                chart.draw(data, options);
            },
            failure: function (r) {
                alert(r.d);
            },
            error: function (r) {
                alert(r.d);
            }
        });
    }
</script>
<asp:RadioButtonList ID="rblChartType" runat="server" AutoPostBack="true" RepeatDirection="Horizontal">
    <asp:ListItem Text="Pie" Value="1" Selected="True" />
    <asp:ListItem Text="Pie-3D" Value="2" />
    <asp:ListItem Text="Doughnut" Value="3" />
</asp:RadioButtonList>
<div id="chart" style="width: 600px; height: 500px;">
</div>

Code

sqlwebmethod

using System;
using System.Configuration;
using System.Data;
using System.Data.SqlClient;
using System.Web.Services;

public class sqlwebmethod
{
    public SqlDataReader dr;

    [WebMethod]
    public IDataReader getdr(string cmd)
    {
        SqlConnection con = new SqlConnection();
        {
            if (con.State == ConnectionState.Open)
            {
                con.Close();
            }
            con.ConnectionString = ConfigurationManager.ConnectionStrings["cs"].ConnectionString;

            if (con.State == ConnectionState.Closed)
            {
                con.Open();
            }
            SqlCommand execmd = new SqlCommand(cmd, con);
            dr = execmd.ExecuteReader(CommandBehavior.CloseConnection);

            if (dr.Read())
            {
                return dr;
            }
            else
            {
                return null;
            }
        }
    }
}

C#

[WebMethod]
public static List<object> GetChartData()
{
    sqlwebmethod sql = new sqlwebmethod();
    string query = "SELECT ShipCity, COUNT(orderid) TotalOrders FROM Orders WHERE ShipCountry = 'USA' GROUP BY ShipCity";
    IDataReader idr = sql.getdr(query);
    List<object> chartData = new List<object>();
    chartData.Add(new object[] { "ShipCity", "TotalOrders" });
    idr.Read();
    while (idr.Read())
    {
        chartData.Add(new object[] { idr["ShipCity"], idr["TotalOrders"] });
    }
    idr.Close();
        
    return chartData;
}

Screenshot