Get Adminhtml quote session using Magento 2.

Magento Native supports multiple Sessions type for frontend and backend (adminhtml) system.

You can get admin Html(backend) quote session using Magento 2 by Magento\Backend\Model\Session\Quote class.

Quote Class is responsible for getting Back end quote in Magento 2 admin panel order processes.

<?php
namespace Jesadiya\BackendQuoteSession\Model;

use Magento\Quote\Model\Quote;
use Magento\Backend\Model\Session\Quote as AdminCheckoutSession;

class BackendQuoteSession
{
    /**
     * @var AdminCheckoutSession
     */
    private $adminCheckoutSession;

    public function __construct(
        AdminCheckoutSession $adminCheckoutSession
    ) {
        $this->adminCheckoutSession = $adminCheckoutSession;
    }

    /**
     * Returns the Quote object made in adminpanel area
     *
     * @return Quote
     */
    public function getCurrentAdminQuote(): Quote
    {
        $quote = $this->adminCheckoutSession->getQuote();

        return $quote;
    }
}

You can get Backend quote using the above function and fetch quote related data.

You can fetch current quote items, quote id, extension attributes related data.