CCBill is a popular payment provider that offers solutions for both adult dating and mainstream dating websites.
In order to get started, you can purchase an integration service in the Marketplace, or you will already have CCBill included in your package starting with PG Dating Pro Liebe, version 2018.12. You will also need to create a merchant account with the CCBill payment gateway.
After that, please follow the instructions from this detailed manual: CCBill DatingPro Module Setup (PDF).
The manual includes information on how to configure your CCBill account, create a new billing form (FlexForms or Standard Forms), and activate this payment option on your dating site.