How to troubleshoot routes Very new to Craft CMS...

My first route, which i think is very simple, is not working, i'm getting a 404 error.  How can I troubleshoot routing?

My settings:

If the URI looks like this:

databases/


Load this template:

library-database-demo-section/index.html
Remove the / at the end of databases/ and it should work.

Technically, index.html is not required either, so you could just use library-database-demo-section.