Hi,
The setting is not available to customize the default contact form.
If you don’t want to use this default contact form, you can install and use Contact Form 7 for your contact page
Contact Form 7
To remove the Contact Form from main right sidebar
Go to the Appearance -> Widgets -> Sidebar Main -> Add Widget
Please check the documentation
https://gracethemes.com/documentation/powerclub-doc/#widgets
Regards
Grace Themes