Put your cgi-bin scripts in the WWW subdirectory named cgi-bin.

If your domain is named company.com, you would then access your scripts as /cgi-company/

To find the path of the program date, type which date. Do this for any program that you need your cgi-bin script to access.

I see lots of perls, which one should I use?

They should all be the same. /usr/local/bin/perl should work nicely. Refer to the Telnet section for additional reference materials. Many cgi scripts come with their own instructions on placement, how to run them, etc.