delphi syntax is very different by C++, but most concepts are shared (not all).
i'm unsure what you need for email. but for sure you need a mail server. buying a domain may be a good idea.
but in the end, if you do it on your own computer, it will have to stay online 24h/day, or the system may not work that well.
you'd better buy an online server. here in italy you can get a basic hosting service for 11€/year, and you just need to install a php application to get the file sharing.