Following code demonstrate how one can add checkboxes on a frame.

Java Code:
Frame frame= new Frame("MyFrame");
Label label = new Label("Choose the languages of your interest:");
Checkbox java=new Checkbox("Java");
Checkbox cpp=new Checkbox("C++");
frame.add(label);
frame.add(java);
frame.add(cpp);
frame.setLayout(new FlowLayout());
frame.setSize(400,100);
frame.setVisible(true);