After many hours of troubleshooting a wireless network, including hardwiring the computer to other the router (in a port with a wire working on another computer, we found a solution!

The solution was simple and it was easy... We went into Network Connections > Disabled Network Bridge > Removed All Network Devices from Network Bridge.

I don't know what the network bridge does, except disable network connections (at least sometimes). So if you're having the same problem of being connected to the access point, yet still having limited or not connectivity, or connected hardwired with a good IP address, yet still not having packets received or at least very few, but packets are being sent, and you've tried all else, this may be something else you can try.