RAXE300 - Replaced old router of different manufacturer, and cannot get this one to work with DYNDNS

I have (or at least I once had) a web page: http:kosmanor.com.  Routing was handled by DYNDNS.  It isn't working now.

The switch was just before I had a calamity that kept me away from everything for 6 months, so I'm past the warranty period.  I'm a bit over my head and can't tell what's working and what isn't.

I can't even figure out what IP number has been assigned to the router by my ISP.  My previous router made all that easy.

But the basic problem is that when I try to access http://kosmanor.com I get "no route to host".  It should be a very simple pure HTML page saying you got here, but you'll need a longer URL to get anything useful.

Can anyone help?