how-to parse csv file with perl

use strict ;

# START FOREACH LINE
#SET HERE THE PATH TO THE FILE
my $inputfile='input.txt' ;

#READ ALL ROWS OF A FILE TO ALIST
open (INPUT, "<$inputfile") || print "could not open the file!\n"; my @lineArray = ;
close INPUT;

#DO SOMETHING TO EACH LINE OF THE FILE
foreach my $line ( @lineArray )
{
my ( $f1 , $f2 , $f3 ) = split ( '\t' , $line ) ;
print "\$f1 , \$f2 , \$f3 , $f1 , $f2 , $f3 " ;
} #eof foreach

# END FOREACH LINE