Hi There @zerotoone.de
Thanks for writing in! Please follow our detailed guide on our knowledge base section here (https://theme.co/apex/forum/t/extension-email-forms/82) which includes setting up your email form with Mailchimp and integration.
If you don't have Footer Widget Areas enabled already, please head over to X -> Theme Options -> Footer -> Footer Widget Areas and enable how many columns you needed.
Then you can access those widget areas by head over to Appearance -> Widgets area and place your email form widget area accordingly.
Hope that helps.