Answer:
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.border.TitledBorder;
public class JustinDillingerHW3 extends JFrame {
//Create text fields and labels
private JTextField jtfFirstName = new JTextField(15);
private JTextField jtfLastName = new JTextField(15);
private JTextField jtfId = new JTextField(2);
private JLabel WelcomeMessage;
public static void main(String[] args){
    JustinDillingerHW3 frame = new JustinDillingerHW3();
    frame.setTitle("Hello User!!");
    frame.setSize(300,250);
    frame.setLocationRelativeTo(null);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setVisible(true);
}
public JustinDillingerHW3(){
    setLayout(new FlowLayout(FlowLayout.LEFT, 10, 20));
    //add labels and text fields to the frame
    add(new JLabel("First Name"));
    add(jtfFirstName);
    add(new JLabel("Last Name"));
    add(jtfLastName);
    add(new JLabel("StudentId"));
    add(jtfID);
    //Create Welcome button
    JButton Welcome = new JButton("Click Here");
    add(Welcome);
    Welcome.addActionListener(new SubmitListener());
    WelcomeMessage = (new JLabel(" "));
    add(WelcomeMessage);
}
class SubmitListener implements ActionListener{
    public void actionPerformed(ActionEvent e){
        String FirstName = jtfFirstName.getText();
        String SurName = jtfLastName.getText();
        WelcomeMessage.setText("Welcome, " + FirstName + " " + SurName);
    }
}
}