Netgear Ac1750 c6300 won't connect

Have had everything setup and working on Comcast for the last few months with no issues. Last night internet went out and havent been able to reconnect. Have followed all the troubleshooting guides, resetting, confirmed no comcast outage, etc and no luck. I can't log into the modem router as it says page can't be displayed. Also followed guide to clear this without success. Odd thing is a few one off sites work like Yahoo but nothing else. Am frustrated and need some guidance.