How to deploy a "web to lead form" without exposing SuiteCRM to the world?

My setup of SuiteCRM is on my local PC and not exposed to the web, and it won’t be. Still, I want to use “web to lead” forms and automatically feed my SuiteCRM database. How can I do that ? Is there a way for example to get the leads in a file on the web site server, download it, and import it in SuiteCRM ? What is the best and easiest process ?