Low ping

How do i know what ping I’m getting on my network between modem device and pc without the use of Ookla …?

Best way to do this is to ping your router. This will normally be 192.168.1.1, 192.168.0.1 or 192.168.1.254.

You can check what the IP of your router / gateway aka modem is by checking the connection properties on your OS.