You want to:

Fetch an url. (Or so you say)

use LWP::Simple

Read a CSV file.

It's not as easy as you think. use Text::xSV

Render dynamic HTML

If your script gets more complicated you might want to try a templating module. there are loads of them on CPAN

Generic notes: I think in this case

next unless $_;
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is much neater than

next if 0 == length($_);
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but if you need that line, you're not reading CSV anyway.

I really have no idea what you mean with "must it be i a form"? There is no form.

As for "Must I use the "my $query = new CGI;" codes" - well, if you're going to parse input, yes. Also, if you use the CGI modules methods $query->request_uri and $query->referer(), that'll trap misspellings of the %ENV entries.