Hi. I am based in the Philippines. My client wants to add a payment method with a gateway service api that leads them to the payment form and then redirects back to the orders complete page after successfuly transaction. Is that possible?
Yes, It is possible, you need to use Shopify Hosted Payment SDK method to integrate a new alternative payment gateway to a Shopify Store. Oganro is a one of the Shopify development agency who provides such a service.