But I cant make it work.
That does not describe the problem.
Is the problem that you don't know how to use a JMenuItem? Do you know how to add an ActionListener to a menu item? Do you know how to create a table? Are you trying to create a popup JDialog to display the table or are you trying to add the JTable to an existing panel in the GUI?
There is no way we can help you because you question is so vague.
All I can suggest it to read the JMenuItem API or the JTable API and you will find links to the Swing tutorial that given examples of using menu items and tables.
Then is you have further questions you can post a
SSCCE with the question showing the problems you are having.