Hi,
I am Magento1 certified developer with "Developer Plus" certification having 8years of working experience in web development, along with almost 2+year of working experience in Magento2 web development, majorly in custom development, theme implementation and migration and site from scratch.
I have gone through your description and checked image that you have sent. Correct me if I have understood the problem wrong.
- You already have payment method for credit card which should redirect you to bank site instead of showing credit card input fields.
I just have a question, After filling up the details if I place an order does it get redirect to bank site now?
Does order gets placed?
I guess payment method that you have configured is wrong, you need to have server hosting payment but instead of that you have configured the wrong one. You might check with module for the same.
Lets discuss in brief at your convenience.
Thanks