Obviously other posts have covered the main points:

1. you meant $_, not @_[$_]
2. even if you'd wanted to index the array, the syntax is $array[$index], not @array[$index]
3. 'use warnings' (or adding -w to your shebang line) should be your first step in troubleshooting (actually the zeroth step, you should always pre-emptively turn it on).

I'd just like to add that I think the problem also owes something to poor choice of variable names. I'm not one to say that using $_ and @_ is always evil, but compare how easy it is to spot the error:

sub total
{
  my @numbers = @_;
  my $total = 0;
  foreach my $value (@numbers) {
    $total += $numbers[$value]; # Wait, what?
  }
  return $total;
}
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