The only place that content from the custom post type will display is in the file that you created single-{post-type}.php. You can show archives of the custom post type by creating archive-{post-type}.php. The template file page.php is not in the template hierarchy for a custom post type.
This comes in handy for showing what templates will be looked for depending on what’s being loaded https://developer.wordpress.org/themes/basics/template-hierarchy/
