You aren't getting a default route. If you use static file configuration then the default route is missing. If you use dhcp/automatic network configuration and a network manager, you might be overriding the route dhcp is giving you.

File configuration usually has a gateway entry. Network manager has an option to accept or change the default route given back by dhcp.

So that is the question, how are you configuring network parameters?

* you haven't mentioned which linux distro - they each have custom hacks making whatever works on source install (or each other) not workable. If you are in a big distro it probably "works their way or no way at all" so seek their instruction - and note they ban people who say it isn't working.

* you haven't mentioned wpa-supplicant.conf

even if you can ping your (wifi enabled cable modem i assume) ...

you have to choose a network choice (in detected list), provide a (modem pin) , provide a password

It's a very typical question "i can ping my wifi modem but get nowhere" if you haven't yet logged in.

Obviously there are thousands of internet documents describing the above i shouldn't repeat here.

This looks like a misconfiguration issue.
The Archer C8 User Guide has an FAQ section with:
that provides a test link.
The MX Linux Users Manual has Section 3.4 Network. It appears that the router is likely working correctly, but the gateway address is not being assigned. Right-click the Network Manager applet > Edit Connections to open up a Settings box. Check the WiFi connection settings, especially that the IPv4 Settings tab has Method: Automatic (DHCP) set.

Network Manager Settings
 

Network manager screenshots attached.

Those NetworkManager settings seem to be correct, except that I also see boxes for Rate and Transmission power on my WiFi tab.
What is the wifi device in your G50-45? It should appear in the output of '/sbin/lspci | grep -i Network'.

Wifi Device
 

Found it in /bin

Try adding a gateway, use the actual LAN IP address for your router

You can put the route in the ipv4 config, but you should not have to do that. Under Additional Static Routes, add
0.0.0.0 0.0.0.0 192.168.1.1

and hit add. This should add the default route (0.0.0.0) to the route table, type ip route to see it.

But once again, you will have to remember this when you change your network configuraton.

Adding routes.
 

When I tried to add the route from the terminal I got:

When I tried adding the route through the network manager the address, (0.0.0.0), was in red and the save button greyed out.

Thank you for your help and your patience.

Some basic checks:
Does 'nmcli device status' show your wireless device is connected?
If so, does /etc/resolv.conf look something like
Does 'dig -x 192.168.1.1' show something like Router.Domain?
Does 'dig @192.168.1.1 www.google.com' return a valid record?

Just ping 192.168.1.1 and do a nmci. By your previous debugging, it seems like the interface should work but not being to set the route seems to indicate that it is not. Reboot to clear the ifconfig counters and restart all networking. Something is very strange.

Running the "sudo route add default gw 192.168.1.1 wlan0" right after booting up fixed the problem. Before I had tethered to my phone and untethered but never rebooted so the network must have remembered. Will I have to make this command run at startup all the time or should I try adding it into the network manager GUI? Thank you for everyones help and patience.

Normally network manager and the dhcp client should create the route but I am not exactly sure what is not working at the moment. It works as expected when connected to the phone so there must be something not configured correctly.