Fairly simple actually,
E.g. On Caltex pumps, the CC terminal on the left, then there's another keypad, screen or no screen on the right, most pumps have it, but not all.

If its the keypad with screen, key in yr preferred amount with that keypad, and you can see it shown on that screen itself,
the CC terminal screen it still shows lift nozzles to pump. You just lift nozzle to pump once u're satisfied with what you entered.

If its just the keypad, without the screen, then the amount you key-in will be the pump screen in the middle (the one with the running amount when u pump), but it'll be flashing, and the CC terminal still shows lift nozzles to pump. You just lift nozzle to pump once u're satisfied with what you entered.

You can even key-in the amount when it's only verifying yr CC, you don't need to wait it to ask you to remove yr card.