Skip payment method selection in Drupal Commerce
You would have to hide the payment method checkout pane via a form alteration, because the payment method still technically needs to be selected for the redirect page to show properly. However, if you just want to remove the "Review" page since you don't need it as an intermediate step for payment method selection, you could just move the payment method checkout pane to the "Checkout" page and disable the default review checkout pane.