Enabling the card type in Chargebee Gateway settings will only display the icon in the hosted page.

Making this change does not necessarily mean that that particular card type(s) will be accepted as it solely depends on whether your gateway provider accepts the particular card type or not.

Below are example screenshots of how this settings reflect on the checkout page for your reference:

Having disabled Discover, and JCB card types, note that the respective icons are not displayed in the checkout page(screenshot below).

Hence, to be able to accept a particular card type, you would need to check with your gateway provider to know the card types they support.