Hello Monks, I have a simple doubt, can anyone pls answer me?

Yes, you can answer this yourself in about 1 minute by reading perlintro or perlrequick, and probably perlfaq or perlmonks

 [digit string] digit string -> Number of digits at the end of the string

#!/usr/bin/perl --
use strict; use warnings; use Data::Dump; use Carp::Always;
use Regexp::English;
my $string = "nPqwe=2456fnraqe=13910feoption"; 
my $rex = Regexp::English
-> remember
    -> digits
-> end
;;;;
print "$rex\n";
while( $string =~ m{$rex}g ){
    print "$1\n";
}
__END__
(?^:(\d+))
2456
13910
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