Explainnation of a Perl CGI Script

I am looking for a freelancer who can help me understand the content of a Perl CGI script. I already have the script, but I need assistance in understanding the script so tha I can easily modify it .

Skills and Experience:
- Strong knowledge of Perl and CGI scripting
- Strong knowledge of Bash Shell scripting
- Experience in understanding and analyzing existing scripts
- Good understanding of data processing, form handling, and file uploading in Perl CGI scripts

Deadline: No specific deadline