The problem that you are encountering is due to the way that
you are trying to print the HTML. The line:- print <<ENDhdr; is going to print everything to STDOUT until it finds a line
the starts with the matching ENDhdr. So you do not require
the print statements on each of the lines.
Another point is that you will require the <FORM>...</FORM> tag
around the input tags.
Things can be made MUCH easier if you were to use the
CGI.pm module eg.

#!/usr/bin/perl
#
use CGI;

$page = new CGI;
my $in;
  if ($ENV{'REQUEST_METHOD'} eq "GET") {
      $in = $ENV{'QUERY_STRING'};
  } else {
      $in = <STDIN>;
  }

  @Texts = ("text1","text2","text3","text4","text5");

print $page->header(); # This outputs the Content-Type stuff
print $page->start_html();
print $page->startform;
print <<ENDhdr;
.....
.....
ENDhdr
print $page->endform();
print $page->end_html();
[download]

Try using perldoc CGI to get more info
Hope this is of some help