Just in case others are stumped with trying to learn how to reveal submitted comments onto a comments page (or any page for this matter), a good starting point to investigate is using the WordPress function wp_list_comments()
There are examples provided on that resource page to get things going in a healthy direction.
I would also include the following debug tactic as a help along the way…
?><pre><?php var_dump( $variable_to_test ); ?></pre><?php
…as mentioned by Q Studio. Thanks for that!
Update
Another good resource to help extend the OOTB comment fields with more fields by WPengineer.com. I’ve tested it out for myself in 2020, and concepts still work.