RBK753S Not Connecting To Internet... Followed All Instructions Too!

For some reason, I cannot get my WiFi Router & Satellites to connect to the Internet.  My cable internet works with my modem when connected directly TO the modem...but if I follow the App directions, shut off the modem, turn it on...plug ethernet to Router, then power router on...WiFi comes up on my phone...but NO Internet.  Not sure 'why'...I'm halfway tech savvy...but this is stumping me.  I called Netgear support...got a guy from India I could BARELY understand and he finally transferred me to "tech support" but all that happened was sitting on the phone for over 1 hour, and "support" never came on...I hung up.  So frustrated...may take this back to Costco...but still can't figure out 'why' the Internet won't come up.  I've got the Internet cable into the router port, with ethernet to my modem...zip.  Any super good "tech" guys out there.  Running windows 10, Android Galaxy S20 phone, everything works...except the Internet WiFi.