Getting "recent posts" operable

I know there’s something simple I’m not doing here that’s causing my problem. As I add a new post to my blog (Weaver 2.2 theme) the previous post moves to the “Recent Posts” widget, as expected. However, a viewer clicking on one of the recent posts to read it is directed to a page that says “Not found”, with a search box appearing. I’ve noticed the same problem when clicking on links when testing my site with search engines.

Any ideas on how I can correct this?

https://www.stupidityinamerica.com

Thanks for any responses.