Please help!

How do I add these three items to my code below?

Create the following screens with their labels and input fields:

• Login screen.
• Add Customer screen.
• Place Order screen

package testweek8; import javafx.application.Application; import javafx.event.ActionEvent; import javafx.event.EventHandler; import javafx.geometry.Insets; import javafx.geometry.Pos; import javafx.scene.Scene; import javafx.scene.control.*; import javafx.scene.layout.HBox; import javafx.scene.layout.VBox; import javafx.scene.text.Font; import javafx.stage.Stage; public class TestWeek8 extends Application { private Label lblHeading1, lblHeading2, lblKey, lblMessage1, lblMessage2; private ComboBox cmbKeys; private TextField txtMessage1, txtMessage2; private Button btnTranslate, btnCopyUp, btnClear; private VBox root; //start public void start(Stage stage) throws Exception { init_Controls(); HBox box1 = new HBox(10); box1.setPadding(new Insets(10)); box1.setAlignment(Pos.CENTER); box1.getChildren().addAll(btnTranslate,btnCopyUp,btnClear); //add Listener btnClear.setOnAction(new MyHandler()); btnTranslate.setOnAction(new MyHandler()); btnCopyUp.setOnAction(new MyHandler()); HBox box2 = new HBox(10); box2.setPadding(new Insets(10)); box2.setAlignment(Pos.CENTER_LEFT); box2.getChildren().addAll(lblKey,cmbKeys); HBox box3 = new HBox(10); box3.setPadding(new Insets(10)); box3.setAlignment(Pos.CENTER_LEFT); box3.getChildren().addAll(lblMessage1,txtMessage1); HBox box4 = new HBox(10); box4.setPadding(new Insets(10)); box4.setAlignment(Pos.CENTER_LEFT); box4.getChildren().addAll(lblMessage2,txtMessage2); root.getChildren().addAll(lblHeading1,lblHeading2,box2,box3,box4,box1); //set window title stage.setTitle("Caesar Cipher JavaFX"); stage.setResizable(false); stage.setScene(new Scene(root, 600, 300)); //show the screen stage.show(); } private void init_Controls() { lblHeading1 = new Label("CAESAR CIPHER TRANSLATION"); lblHeading1.setFont(new Font("ARIAL", 20)); lblHeading2 = new Label("Select a key enter message press 'Translate'"); lblHeading2.setFont(new Font("ARIAL", 14)); lblKey = new Label("Key"); lblMessage1 = new Label("Message 1:"); lblMessage2 = new Label("Message 2:"); cmbKeys = new ComboBox<>(); cmbKeys.getItems().addAll(-3, -2, -1, 0, 1, 2, 3); txtMessage1 = new TextField(); txtMessage1.setMinWidth(400); txtMessage1.setPromptText("Enter message to be translated"); txtMessage2 = new TextField(); txtMessage2.setMinWidth(400); txtMessage2.setPromptText("Translated message will display here"); btnTranslate = new Button("Translated"); btnCopyUp = new Button("Copy Up"); btnClear = new Button("Clear"); root = new VBox(10); root.setPadding(new Insets(10)); root.setAlignment(Pos.CENTER_LEFT); } //function to encode plain text to cipher text private String encode(String plain, int key) { StringBuilder cipher = new StringBuilder(); char pchar; int len = plain.length(); //encoding character by character for (int i = 0; i < len; i++) { pchar = plain.charAt(i); if (pchar >= 'A' && pchar <= 'Z') { //upper case alphabet encoding pchar -= 'A'; pchar += key; pchar %= 26; pchar += 'A'; } else if (pchar >= 'a' && pchar <= 'z') { //lower case alphabet encoding pchar -= 'a'; pchar += key; pchar %= 26; pchar += 'a'; } cipher.append(pchar); } return new String(cipher); //return encoded message } //function to decode cipher text private String decode(String cipher, int key) { StringBuilder plain = new StringBuilder(); char cchar; int t; int len = cipher.length(); //decode character one by one for (int i = 0; i < len; i++) { cchar = cipher.charAt(i); if (cchar >= 'A' && cchar <= 'Z') { //decode upper case alphabet cchar -= 'A'; t = cchar - key; cchar = (char) (t < 0 ? (t + 26) : t); cchar %= 26; cchar += 'A'; } else if (cchar >= 'a' && cchar <= 'z') { //decode lower case alphabet cchar -= 'a'; t = cchar - key; cchar = (char) (t < 0 ? (t + 26) : t); cchar %= 26; cchar += 'a'; } plain.append(cchar); } return new String(plain); //return plain message } public static void main(String[] args) { //start application launch(args); } class MyHandler implements EventHandler { @Override public void handle(ActionEvent event) { String message1, message2; int key; if(event.getSource().equals(btnClear)) { cmbKeys.getSelectionModel().clearSelection(); cmbKeys.getItems().clear(); txtMessage1.setText(""); txtMessage2.setText(""); txtMessage1.setPromptText("Enter message to be translated"); txtMessage2.setPromptText("Translated message will display here"); } if(event.getSource().equals(btnTranslate)) { try { if(cmbKeys.getSelectionModel().getSelectedIndex()==-1) throw new IllegalArgumentException("Please select a key"); if(!txtMessage1.getText().equals("")) { key = cmbKeys.getSelectionModel().getSelectedItem(); message1 = txtMessage1.getText(); message2 = encode(message1,key); txtMessage2.setText(message2); } if(!txtMessage2.getText().equals("")) { key = cmbKeys.getSelectionModel().getSelectedItem(); message2 = txtMessage2.getText(); message1 = decode(message2,key); txtMessage1.setText(message1); } } catch (IllegalArgumentException ex) { Alert alert = new Alert(Alert.AlertType.WARNING,ex.getMessage()); alert.show(); } } if(event.getSource().equals(btnCopyUp)) { try { message2 = txtMessage2.getText(); message1 = message2; txtMessage1.setText(message1); txtMessage2.setText(""); } catch (IllegalArgumentException ex) { Alert alert = new Alert(Alert.AlertType.WARNING,ex.getMessage()); alert.show(); } } } } }