Best practices to embed general components(site components) in an Adaptive Form

[#1]

I am working on developing an Adaptive form in AEM. We already have a sites component which we drag into the parsys system on the site pages. However in the AEM forms parsys I am unable to include the site component(General). Its only allowing me to include the adaptive form components. Is there a way to include the sites component within AEM forms or do I need to convert the sites component to an adaptive form component ?

[#2]

Thanks for the response, that helped us. I think the issue is when we create a AEM form template using template editor. In this case we dont have a design mode present. Instead we have content policies present where we can define the design properties. I need to take this route to include the general components in design mode so that I have them in the side kick.

Below link has helped me understanding the content policies:

Page Templates - Editable