using System;

public class Program

{

    public static void Main()

    {

        string inpData="Hello welcome to welcome my first Hello Welcome Console Application";

        string strSearch = "no";

        int countWord=0;

        inpData = inpData.ToLower();

        strSearch = strSearch.ToLower();

        Boolean chkWord=false;

        for(int i=0 ; i<inpData.Length; i++){ 

            chkWord=false;

            if(inpData[i] == strSearch[0]){

                chkWord = true;

                for(int j =1 ; j<strSearch.Length; j++){

                    if((i+j)<inpData.Length && inpData[i+j] != strSearch[j]){

                        chkWord = false;

                        break;

                     }

                }

            } 

            if(chkWord==true ){

                Console.WriteLine("Found  at  index=" + i);

                countWord++;

            } 

        }

​

        Console.WriteLine("found word in string ="+countWord);

    }

}