Can we get thumbnails on related posts setting?

Jetpack automatically picks those thumbnails for you, based on the images you’ve used in the original post. To make sure a specific image is used as the Related Post thumbnail, you’ll need to set that image as the Featured Image in the original post. If the image is large enough, it will then be used as Related Post Thumbnail.

If you also want to create a default image that would be used when no image was inserted in the original post, you can follow the instructions here:
https://jeremy.hu/jetpack-missing-images-related-posts/

I hope this helps. Are there any other options you’d like to have in Jetpack’s Related Posts?