How I Put The Button On The Left?

import java.awt.event.KeyEvent;
import java.util.HashSet;
import javax.swing.AbstractButton;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingConstants;

public class Calendar {

    public static void main(String[] args) {
        //Construtor de JFrame
        JFrame frame = new JFrame();
        frame.setSize(300, 300);
        frame.setTitle("Calendário");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
        JButton b1 = new JButton("MODIFICAR");
        JPanel painel = new JPanel();
        
        frame.add(painel);
        painel.add(b1);

    }

}