With Yoast SEO Plugin you can review your Cornerstone Content List where you can easily find the total backlinks to your Cornerstone Content & the links from your Cornerstone Content to other subpages also. Read more:-
https://seattlewebsitedesignagency.wordpress.com/2021/05/14/what-is-cornerstone-content-strategy-how-to-build-an-effective-cornerstone-content-strategy-egoodmedia/