Internal linking is the process of maintaining the website link for internal structure. linking the website internal link with own post is the best way to improve internal linking structure this also work more for SEO as do follow links.
Internal Links are hyperlinks that factor at (target) the same website as the domain that the link exists on (source). In basic terms, an internal link is one that points to one more page on the same website.
It's about using keywords to link one page on your website to another when they are related. e.g. you have a page that talks about "red widgets" and on that page you mention "blue widgets" so you would link this to the page where you talk more about blue widgets.