Hi user-i,

Thanks for details.

1. There is no way to apply Custom Single Product Layouts to Single Post, these are 2 separate Post Types. I also you created 2 Custom Template for blog posts, you can select these.

2. Regarding creating new post type, please refer to this article for more details https://www.wpbeginner.com/wp-tutorials/how-to-create-custom-post-types-in-wordpress/

Regards,