Custom Payment Method Isn’t validate before click Place order button

Magento 2.3.5 version application using custom payment method module. This module refer from code here

view/frontend/web/template/payment/llamacoin.html

    <!-- Render the native credit card form. -->
    <form class="form" data-bind="attr: {'id': getCode() + '-form'}">
        <!-- ko template: 'Magento_Payment/payment/cc-form' --><!-- /ko -->
    </form>

    <div class="checkout-agreements-block">
        <!-- ko foreach: $parent.getRegion('before-place-order') -->
        <!-- ko template: getTemplate() --><!-- /ko -->
        <!--/ko-->
    </div>

    <div class="actions-toolbar">
        <div class="primary">
            <button data-role="review-save"
                    type="submit"
                    data-bind="
                    attr: {title: $t('Place Order')},
                    enable: (getCode() == isChecked()),
                    click: placeOrder,
                    css: {disabled: !isPlaceOrderActionAllowed()}
                    "
                    class="action primary checkout"
                    disabled>
                <span data-bind="i18n: 'Place Order'"></span>
            </button>
        </div>
    </div>

full code html file here

view/frontend/web/js/view/payment/method-renderer/llamacoin.js

define([
        'jquery',
        'Magento_Payment/js/view/payment/cc-form'
    ],
    function ($, Component) {
        'use strict';

        return Component.extend({
            defaults: {
                template: 'ClassyLlama_LlamaCoin/payment/llamacoin'
            },

            context: function() {
                return this;
            },

            getCode: function() {
                return 'classyllama_llamacoin';
            },

            isActive: function() {
                return true;
            }
        });
    }
);

Checkout page show Payment method look like

This knockout js calling input field to html

 <!-- ko template: 'Magento_Payment/payment/cc-form' --><!-- /ko -->

I don’t know more about this, please help me any solution

Where will get input field (“payment credit card number”, “expiration date”) data customize?

How can I validate and show error message using frontend technology “payment credit card number”, “expiration date” when customer click “Place Order” ?

Thanks for advance