Undefined subroutine &main::strftime called at geo_db.pl line 2.

Can't locate object method "new" via package "WWW::Curl::easy" (perhaps you forgot to load "WWW::Curl::easy"?) at geo_db.pl line 14.

Both these errors are consequences of the same basic fact: you are using functions from modules that are not loaded. Before you use functions from a module, you need to explain perl that you will be using these modules. Perl being what it is, that means you just need to tell it so:

#!/usr/bin/perl -w

use Posix; # strftime() lives here
use WWW::Curl::easy; # WWW::Curl::easy::new() lives here
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Judging from these questions, you might benefit from reading a good book on learning Perl. Again, Perl being what it is, there is actually a good book called Learning Perl, which I can recommend heartily.