Orbi RBR40 and Arris Surfboard 8200 connection issue

1st, I'm not tech savy AT ALL!   Just got the Arris Surfboard with Docsis 3.1.  Connected it to the Orbi RBR40 router.  Have been talking to my cable provider trying to find out why I cannot get our Rokus throughout our house to show any internet.

The Arris and Orbi are showing connect (earlier they were showing connected without internet).  I've rebooted both the cable modem and the Orbi Router, and the unplugged the Roku from the TV and Roku itself.  Synched the satellite Orbi to the base, but still do not get internet.  On my computer, next to the modem and router shows connected and I can get on the internet, but anything outside this room, I cannot.    Spectrum (who I absolutely HATE) isn't helping.   Said call Netgear.  I no longer have free support with them.  So, I am hoping someone here can help.    Didn't know if the Arris was too much for the Orbi?   Maybe have to take back and get get something with Docsis 3.0 instead.

Please help, but in instructions I can understand.   I've tried to log onto the Orbi.com and Orbilogin.com, but it is not accepting my login, serial number or security settings!!!!!!!!   Totally frustrated.