Shortening code to create a JFrame
The user has working code (I assume), but they haven't even started writing the logic for their game. They've just instantiated Java's version of a main window/frame.
I feel like this is the same as me asking, "Please review my OS Kernel" and then all I give you is this:
int main (void)
{
return 0 ;
}
For my answer, I did my best to explain possible next steps, but there's not really much to advise on.
I'm not advocating that code submitted for review must be complete, but I think there should be a decent amount of progress. Otherwise we can only give design tips that may be better off being posted on Programmers Stack Exchange.