Product Calendar

1: Config

Style: Modern, Classic

2: Customize Template

Read here to know how to customize template in child theme

You can customize template in

// Style: Modern
plugins/ova-brw/ovabrw-templates/modern/single/detail/ovabrw-product-calendar.php

// Style: Classic
plugins/ova-brw/ovabrw-templates/single/calendar.php