Connecting Payment gateway with code

Hi, i’d like to add the payment gateway, Citrus Pay, to one of the dynamic pages in my website, so i contacted the wix support, and they said it can’t be done without using wix code.

So, what i intend to do is basically, my users shall select package and programs from the dropdown menu, and based on the selection, the price differs, so i want to redirect them to the payment gateway to make the complete payment using the ‘proceed to payment’ button.

Please suggest something so i can make this possible with wix code.

Take a look at the following examples: