I inherited a wordpress site and need someone to point me in the right direction

Hi, I inherited a website omgjakarta.com It looks like it is running on the Valenti theme.

I am new to wordpress having previously used Magento and Joomla on other sites we own.

When I go to edit a post that is showing a page on the site I get the following fields I can fill in http://prntscr.com/eub23v I would like to know how I can edit these fields circled in red so that they are not compulsory fields and also how I might change the fields name. The fields appear on this page of the site http://omgjakarta.com/barong-bar/

In joomla i would go into the source code but I am not sure how to do that with Wordpress.

Would appreciate any guidance.

Best regards Jim