1<?php echo wp_get_attachment_image(300, array('800', '600'), "", array("class" => "image")); ?>
2
1<img width="700" height="466" src="example.com/wp-content/uploads/2020/02/image.png" class="image attachment-700x600 size-700x600" alt="" srcset="example.com/wp-content/uploads/2020/02/image.png 800w, example.com/wp-content/uploads/2020/02/image-png-1-300x200.png 300w" sizes="(max-width: 700px) 100vw, 700px">
2