Thank you for using our solution. Please note that Bitnami packages and configures already existing applications. However, we can only offer support and help on basic and most frequent application configurations. Always based on the default configuration or on our guides.
You can use a plugin like https://wordpress.org/plugins/kali-forms/ or create your page, like this tutorial https://www.webdesign.org/how-to-create-contact-page-template-in-your-wordpress-theme.22210.html
If you are a beginner I recommend some plugin.
I hope that helps you,