Command line arguments are passed in to the program using a special array. See @ARGV in perlvar. Or, you may play with code something like:

#cli.pl
print "$_: $ARGV[$_]\n" for 0..$#ARGV;
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$ perl cli.pl one two three
0: one
1: two
2: three
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If you want to use a more sophisticated command line, look at Getopt::Long.