Use the \Magento\Store\Model\StoreManagerInterface::getStores()
method:
By default it is implemented as:
A usage example:
/** @var \Magento\Framework\App\ObjectManager $om */
$om = \Magento\Framework\App\ObjectManager::getInstance();
/** @var \Magento\Store\Model\StoreManagerInterface|\Magento\Store\Model\StoreManager $storeManager */
$storeManager = $om->get('Magento\Store\Model\StoreManagerInterface');
$storeManager->getStores($withDefault = false);