The administration (definition of periods) of the calendar is done on shared-house.com website (also free).
You can use the module in combination with a dedicated page on your joomla webpage. You can then redirect all inquiries or reservation requests to any contact form on your website or use the contact form proposed with the booking calendar.
Also, on the website, you will find a tutorial that explains how to embed on your Joomla website the "full page" availability calendar with contact form. You can use it in combination with this module. For this, just include the "full page" calendar on a new article on your site, then adjust the parameters of the module to change the target of the inquiry link to this new article.
Once the module is downloaded on your site, you need to change the "ad number" parameter: change it to your own ad number on shared-house.com website (default ad number is a demo number). To get your ad number, just register for free on shared-house.com website.