Install the Approval Process feature

<?php

namespace Pyz\Shared\QuoteApproval;

use Generated\Shared\Transfer\QuoteTransfer;
use Spryker\Shared\QuoteApproval\QuoteApprovalConfig as SprykerQuoteApprovalConfig;

class QuoteApprovalConfig extends SprykerQuoteApprovalConfig
{
    /**
     * @return string[]
     */
    public function getRequiredQuoteFieldsForApprovalProcess(): array
    {
        return [
            QuoteTransfer::BILLING_ADDRESS,
            QuoteTransfer::PAYMENT,
        ];
    }
}

<?php

namespace Pyz\Client\MultiCart;

use Generated\Shared\Transfer\QuoteTransfer;
use Spryker\Client\MultiCart\MultiCartConfig as SprykerMultiCartConfig;

class MultiCartConfig extends SprykerMultiCartConfig
{
    /**
     * @return array<string|array<string>>
     */
    public function getQuoteFieldsAllowedForCustomerQuoteCollectionInSession(): array
    {
        return array_merge(parent::getQuoteFieldsAllowedForCustomerQuoteCollectionInSession(), [
            ...
            QuoteTransfer::QUOTE_APPROVALS,
            ...
        ]);
    }
}

<?php

namespace Pyz\Client\Permission;

use Spryker\Client\Permission\PermissionDependencyProvider as SprykerPermissionDependencyProvider;
use Spryker\Client\QuoteApproval\Plugin\Permission\ApproveQuotePermissionPlugin;
use Spryker\Client\QuoteApproval\Plugin\Permission\PlaceOrderPermissionPlugin;
use Spryker\Client\QuoteApproval\Plugin\Permission\RequestQuoteApprovalPermissionPlugin;

class PermissionDependencyProvider extends SprykerPermissionDependencyProvider
{
    /**
     * @return \Spryker\Shared\PermissionExtension\Dependency\Plugin\PermissionPluginInterface[]
     */
    protected function getPermissionPlugins(): array
    {
        return [
            new RequestQuoteApprovalPermissionPlugin(),
            new PlaceOrderPermissionPlugin(),
            new ApproveQuotePermissionPlugin(),
        ];
    }
}

<?php

namespace Pyz\Zed\Permission;

use Spryker\Zed\Permission\PermissionDependencyProvider as SprykerPermissionDependencyProvider;
use Spryker\Zed\QuoteApproval\Communication\Plugin\Permission\ApproveQuotePermissionPlugin;
use Spryker\Zed\QuoteApproval\Communication\Plugin\Permission\PlaceOrderPermissionPlugin;

class PermissionDependencyProvider extends SprykerPermissionDependencyProvider
{
    /**
     * @return \Spryker\Shared\PermissionExtension\Dependency\Plugin\PermissionPluginInterface[]
     */
    protected function getPermissionPlugins()
    {
        return [
            new PlaceOrderPermissionPlugin(),
            new ApproveQuotePermissionPlugin(),
        ];
    }
}

<?php

namespace Pyz\Zed\Cart;

use Spryker\Zed\Cart\CartDependencyProvider as SprykerCartDependencyProvider;
use Spryker\Zed\QuoteApproval\Communication\Plugin\Cart\SanitizeQuoteApprovalQuoteLockPreResetPlugin;

class CartDependencyProvider extends SprykerCartDependencyProvider
{
    /**
     * @return \Spryker\Zed\CartExtension\Dependency\Plugin\QuotePreUnlockPluginInterface[]
     */
    protected function getQuoteLockPreResetPlugins(): array
    {
        return [
            new SanitizeQuoteApprovalQuoteLockPreResetPlugin(),
        ];
    }
}

<?php

namespace Pyz\Zed\Quote;

use Spryker\Zed\Quote\QuoteDependencyProvider as SprykerQuoteDependencyProvider;
use Spryker\Zed\QuoteApproval\Communication\Plugin\Quote\QuoteApprovalExpanderPlugin;
use Spryker\Zed\QuoteApproval\Communication\Plugin\Quote\QuoteApprovalQuoteFieldsAllowedForSavingProviderPlugin;
use Spryker\Zed\QuoteApproval\Communication\Plugin\Quote\RemoveQuoteApprovalsBeforeQuoteDeletePlugin;

class QuoteDependencyProvider extends SprykerQuoteDependencyProvider
{
    /**
     * @return \Spryker\Zed\QuoteExtension\Dependency\Plugin\QuoteWritePluginInterface[]
     */
    protected function getQuoteDeleteBeforePlugins(): array
    {
        return [
            new RemoveQuoteApprovalsBeforeQuoteDeletePlugin(),
        ];
    }

    /**
     * @return \Spryker\Zed\QuoteExtension\Dependency\Plugin\QuoteExpanderPluginInterface[]
     */
    protected function getQuoteExpanderPlugins(): array
    {
        return [
            new QuoteApprovalExpanderPlugin(),
        ];
    }

    /**
     * @return \Spryker\Zed\QuoteExtension\Dependency\Plugin\QuoteFieldsAllowedForSavingProviderPluginInterface[]
     */
    protected function getQuoteFieldsAllowedForSavingProviderPlugins(): array
    {
        return [
            new QuoteApprovalQuoteFieldsAllowedForSavingProviderPlugin(),
        ];
    }
}

<?php

namespace Pyz\Zed\Checkout;

use Spryker\Zed\Checkout\CheckoutDependencyProvider as SprykerCheckoutDependencyProvider;
use Spryker\Zed\QuoteApproval\Communication\Plugin\Checkout\QuoteApprovalCheckoutPreConditionPlugin;

class CheckoutDependencyProvider extends SprykerCheckoutDependencyProvider
{
    /**
     * @param \Spryker\Zed\Kernel\Container $container ’
     *
     * @return \Spryker\Zed\CheckoutExtension\Dependency\Plugin\CheckoutPreConditionPluginInterface[]
     */
    protected function getCheckoutPreConditions(Container $container)
    {
        return [
            new QuoteApprovalCheckoutPreConditionPlugin(),
        ];
    }
}

<?php

namespace Pyz\Yves\CheckoutPage;

use SprykerShop\Yves\CheckoutPage\CheckoutPageDependencyProvider as SprykerShopCheckoutPageDependencyProvider;
use SprykerShop\Yves\QuoteApprovalWidget\Plugin\CheckoutPage\QuoteApprovalCheckerCheckoutAddressStepEnterPreCheckPlugin;
use SprykerShop\Yves\QuoteApprovalWidget\Plugin\CheckoutPage\QuoteApprovalCheckerCheckoutPaymentStepEnterPreCheckPlugin;

/**
 * @method \Pyz\Yves\CheckoutPage\CheckoutPageConfig getConfig()
 */
class CheckoutPageDependencyProvider extends SprykerShopCheckoutPageDependencyProvider
{
    /**
     * @return \SprykerShop\Yves\CheckoutPageExtension\Dependency\Plugin\CheckoutAddressStepEnterPreCheckPluginInterface[]
     */
    protected function getCheckoutAddressStepEnterPreCheckPlugins(): array
    {
        return [
            new QuoteApprovalCheckerCheckoutAddressStepEnterPreCheckPlugin(),
        ];
    }

    /**
     * @return \SprykerShop\Yves\CheckoutPageExtension\Dependency\Plugin\CheckoutPaymentStepEnterPreCheckPluginInterface[]
     */
    protected function getCheckoutPaymentStepEnterPreCheckPlugins(): array
    {
        return [
            new QuoteApprovalCheckerCheckoutPaymentStepEnterPreCheckPlugin(),
        ];
    }
}

<?php

namespace Pyz\Yves\ShopApplication;

use SprykerShop\Yves\QuoteApprovalWidget\Widget\QuoteApprovalStatusWidget;
use SprykerShop\Yves\QuoteApprovalWidget\Widget\QuoteApprovalWidget;
use SprykerShop\Yves\QuoteApprovalWidget\Widget\QuoteApproveRequestWidget;
use SprykerShop\Yves\ShopApplication\ShopApplicationDependencyProvider as SprykerShopApplicationDependencyProvider;

class ShopApplicationDependencyProvider extends SprykerShopApplicationDependencyProvider
{
    /**
     * @return string[]
     */
    protected function getGlobalWidgets(): array
    {
        return [
            QuoteApprovalStatusWidget::class,
            QuoteApproveRequestWidget::class,
            QuoteApprovalWidget::class,
        ];
    }
}

<?php

namespace Pyz\Yves\ShopApplication;

use SprykerShop\Yves\QuoteApprovalWidget\Plugin\Provider\QuoteApprovalControllerProvider;
use SprykerShop\Yves\ShopApplication\YvesBootstrap as SprykerYvesBootstrap;

class YvesBootstrap extends SprykerYvesBootstrap
{
    /**
     * @param bool|null $isSsl
     *
     * @return \SprykerShop\Yves\ShopApplication\Plugin\Provider\AbstractYvesControllerProvider[]
     */
    protected function getControllerProviderStack($isSsl)
    {
        return [
            new QuoteApprovalControllerProvider($isSsl), #SharedCartFeature
        ];
    }
}