what is broken link and innner links?
Internal links are links to other pages within the site, and non-working links are links to non-existent pages.
If you delete the article nor URL of that post, that post URL will consider as broken link or 404 error link.
Internal Link means making hyperlink to the keyword anchor text which is link back to the another inner pages of website.
Broken links are links which no more exists from the webpage it was built. These links are harmful for your website and should be recovered immediately.