Hello @DeliquaI ,
PayPal and Stripe are the available options for the Online store, part of the Website Builder integration. For guidance on connecting your existing PayPal and Stripe accounts for payment processing, I'd recommend looking at this article.
For other assistance regarding the Online Store-side of this process, I'd recommend speaking with the Website Builder integration's support team.
Creating an Online Store via the Website Builder
Creating a Shoppable Landing Page in your Constant Contact account
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