Not connecting to wamp server and throwing NetworkOnMainThreadException

Question 1

Well i have done your task just copy and paste it.Its complete task.If you still got any errors comment here.

public class Confirm_instant_top_up extends Activity {
TextView network;
TextView names;
TextView amount;
TextView phone_number;
TextView email_address;
String ntwk; 
String nms;
String amt;
String phone;
String email;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.confirm_instant_top_up);
network = (TextView) findViewById(R.id.network);
names = (TextView) findViewById(R.id.names);
amount = (TextView) findViewById(R.id.amount);
phone_number = (TextView) findViewById(R.id.phone_number);
email_address = (TextView) findViewById(R.id.email_address);

Intent intent = getIntent();

 ntwk = intent.getStringExtra("network");
 nms = intent.getStringExtra("names");
 amt = intent.getStringExtra("amount");
 phone = intent.getStringExtra("phone");
 email = intent.getStringExtra("email");

network.setText(ntwk);
names.setText(nms);
amount.setText(amt);
phone_number.setText(phone);
email_address.setText(email);       
Button btnOk = (Button) findViewById(R.id.btn_ok);
btnOk.setOnClickListener(new View.OnClickListener() {

      @Override
      public void onClick(View v) {
          BackGroundTask task = new BackGroundTask();
            task.execute();     

      }

    });

    class BackGroundTask extends AsyncTask<String,Void,Void> {

        public BackGroundTask()
        {
            super();
        }

        @Override
        protected void onPreExecute() {

        }

        @Override
        protected Void doInBackground(String...params) {

            if(ntwk.length()>0) {
                HttpClient httpclient = new DefaultHttpClient();
                HttpPost httppost = new HttpPost("http://10.0.2.2/test/confirmPayment.php");

                try {
                    List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(2);                            
                    nameValuePairs.add(new BasicNameValuePair("network", ntwk));
                        nameValuePairs.add(new BasicNameValuePair("names", nms));
                        nameValuePairs.add(new BasicNameValuePair("amount", amt));
                        nameValuePairs.add(new BasicNameValuePair("phone_number", phone));
                        nameValuePairs.add(new BasicNameValuePair("email_address", email));
                        httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
                        httpclient.execute(httppost);
                        Toast.makeText(getBaseContext(),"Sent",Toast.LENGTH_SHORT).show();
                } catch (ClientProtocolException e) {
                    e.printStackTrace();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            } else {
                //display message if text field is empty
                Toast.makeText(getBaseContext(),"All fields are required",Toast.LENGTH_SHORT).show();
            }
            return null;

        }
        @Override
        protected Void onPostExecute() {

            return null;
        }

    }
         }
     }

Also dont forget to add permissions in the AndroidManifest.xml

 <uses-permission android:name="android.permission.INTERNET" />
 <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

Question 2

You're trying to execute an Http request on the UI Thread. You should use an AsyncTask for that.

Example:

public void onClick(View v) {
MyAsyncTask myAsyncTask = new myAsyncTask();
myAsyncTask.link(this);
myAsyncTask.execute(new String[]{ntwk, nms, amt, phone, email});
}

And declare this class as an internal or external class :

public class MyAsyncTask extends AsyncTask<String, Void, Void> {

WeakReference<Context> ctx;

public void link(Context ctx){
    this.ctx= new WeakReference<Context>(ctx);
}

@Override
protected Void doInBackground(String... params) {

        if(params[0].length()>0) {
                HttpClient httpclient = new DefaultHttpClient();
                HttpPost httppost = new HttpPost("http://10.0.2.2/test/confirmPayment.php");

                try {
                    List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(2);                            
                    nameValuePairs.add(new BasicNameValuePair("network", params[0]));
                        nameValuePairs.add(new BasicNameValuePair("names", params[1]));
                        nameValuePairs.add(new BasicNameValuePair("amount", params[2]));
                        nameValuePairs.add(new BasicNameValuePair("phone_number", params[3]));
                        nameValuePairs.add(new BasicNameValuePair("email_address", params[4]));
                        httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
                        httpclient.execute(httppost);
                        Toast.makeText(ctx.get(),"Sent",Toast.LENGTH_SHORT).show();
                } catch (ClientProtocolException e) {
                    e.printStackTrace();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            } else {
                //display message if text field is empty
                Toast.makeText(ctx.get(),"All fields are required",Toast.LENGTH_SHORT).show();
            }

    return null;
}
}

And of course as @TalhaQ has mentioned, don't forget to add the permissions to the manifest.

<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />