I'm not sure what you need. To count the number of occurrences of "finding" in a case insensitive way would require the /i switch for case_insensitive and then the /g switch to keep going globally.
There is a critter, called the goatse operator, "=()=" that will give the scalar count of the number of matches. You can read about it here: goatse operator. Or just look at the code and play with it..
my $x = "Finding fiNding fIndinG finding";
my $count = () = $x =~ /finding/ig;
print "$count\n"; #prints 4