How do I connect Windows Firewall to home network

I am running Win7 Pro 64bit (My Grandson's PC). The problem is that when he opens Chrome he can get Google & Gmail but gets an error when he tries to go anywhere else. The error tells me that I can't connect to the proxy server. I have tried changing the LAN settings but that doesn't work. It was suggested I check Windows Defender & Windows Firewall. Defender is out of date & will not turn on. Firewall says connected to Public but Home Network is not connected. I can't seem to find a way to connect it. He uses Windows security Essentials.

I hope someone can help me with this. He is 14 & is very discouraged & impatient because I can usually fix his problems but I am lost on this.

Many Thanks,
MamaWolf

I have tried changing the LAN settings but that doesn't work

What did you change them to? Usually, unless an ISP otherwise specifies, the first item should be checked about "Automatically detect......" and nothing else. I've found if the Proxy section has checkmarks, and the ISP doesn't require them, that infections can cause that and can prevent opening Web sites.

That's what I did. I checked Automatically Detect & unchecked the proxy section. I close chrome & reopen it & those settings have reverted to what they were before I changed them. I also tried restarting the PC after I changed the Chrome settings.