must implement the inherited abstract method java.awt.event.ActionListener.actionPerformed(java .awt.event.ActionEvent)
Read the tutorial I posted in post#24
Or remove the implements ActionListener phrase from the class definition

[line: 44]
Error: Syntax error, insert "}" to complete MethodBody
The compile is telling you to insert a } at line 44

[line: 148]
Error: Void methods cannot return a value
Either change the definition of the method that line 148 is inside of
or change the return statement to not return a value.

[line: 148]
Error: Cannot refer to a non-final variable guess inside an inner class defined in a different method
Change the variable to be final.