Just My try,

Note: This below code does not work if the words contain comma's inbetween.

use strict;
my @array;
while (<DATA>) {
    chomp;
    s,",,g;
    push @array , [ split/[:,]\s?/];
}

__DATA__

COLUMN_A: "Y","N"
COLUMN_B:
COLUMN_C: "something", "something else", "and more"
[download]

Murugesan

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s,,,s,y,y,,,s,,yyymssusyyyyyryyssuysyyysygyeypsyaynyss,s,,,y,y,,d,y,s,,d,y,p,s,d&&print