Depends upon the connection you want to monitor.
There is more than 1. There is generally a MOCa connection between the router and the ONT, and you can see what the speed on that is is from the router at http://192.168.1.1
System Monitoring>system log. The log will give you both the MOCa uplink and downlink speeds.
The speed you are provisioned from at the ONT is not available from the router. You usually have to run a number of speed tests with different servers, and the fastest will give you a good idea of what speed you are provisioned for.
My guess is you are interested in what your connection to Verizon is, and nothing at the router can provide that information.
The quickest and easiest way to check your speed is to simply go to a speed test web site with a hard wired computer.
I would run the test on at least two of those. I personally like speedtest.net best but YMMV.
This is assuming that you mean that you want to check your internet speeds.