You can know the Backorders status of the Product using Magento 2 by Product object.
First Load Product Object by product id or SKU. Now Fetch the extension attributes value of the Stock item from the Product object.
You can retrieve the value of the status of the backorders by Magento 2 with a return available value of 0, 1 and 2. Continue reading “How to get product backorders status in Magento 2?”