Comments are only for Blog posts. They are not for Pages, so you cannot see them in pages section.
If you want to display comments in your pages, you need to do the following:
1. Create a new category of posts and name it “Pages”(just an example)
2. Exclude that category from your regular posts loop.
3. Insert new posts in that category instead of pages.
4. Call the titles of each post in that category to add to the menu, if you need menu for each page.
5. Each menu item should link to the permalink of the post in your “pages” category.
By this way you can include comments in the pages section as well
