1. Text::Iconv is optional.

2. This code prints only column 0 (zero) or 'A'

use strict;
use warnings;

use Spreadsheet::XLSX;

my $excel = Spreadsheet::XLSX->new('test.xlsx');

my $col = 0; # Read col A , $col has to be a number

foreach my $sheet (@{$excel->{Worksheet}}) {

    printf("Sheet: %s\n", $sheet->{Name});
    $sheet->{MaxRow} ||= $sheet->{MinRow};

    foreach my $row ( $sheet->{MinRow} .. $sheet->{MaxRow} ) {

        my $cell = $sheet->{Cells}[$row][$col];
        if ($cell) {
            print $cell->{Val}, "\n";
        }
    }
}
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In English: for each sheet, for each row print cell contents at (row,col) where col is a constant.