Do you mean this?

form( $num);
...
sub form
  { my $game= shift; # if you have several parameters use
                     # my( $p1, $p2)= @_;
   ...
  }
[download]

You should seriously consider getting a book if you want to learn Perl: Learning Perl and Elements of Programing with Perl are good choices.

Update: considering the names of your subs/variables and the other question you asked I would also strongly advise you to use the CGI module and to read its docs, plus Ovid's Web Programing with Perl course. If you are using one of Matt's scripts you might also want to have a lokk at NMS for state of the art replacements