I downloaded this plugin and it works good, but I have an older website run on WordPress and I’m wondering if I downloaded this plugin would it automatically update all the pages that exists or would I have to go through and manually change the links?

https://www.ads-software.com/plugins/append-extensions-on-pages/

The extension is included inappropriately to pages that show up in the URL hierarchy because they have children, such as will image attachment pages. So for instance https://www.mydomain.com/media.html/myattachmentpage/.

It would work for me if it appended the extension to the end of the URL like this: https://www.mydomain.com/media/myattachmentpage.html.

https://www.ads-software.com/plugins/append-extensions-on-pages/