Need help creating a network bridge

Alright, nevermind. It seems whenever I have the bridge properly set up in a way that my nintendo gets internet via ethernet, I can no longer get internet on my desktop PC. Is this working as usual? Do I have no way to get internet to both devices at the same time? I’m about willing to let someone do this for me or go out and buy a physical network switch to get internet to both devices, this is getting kind of ridiculous. Why was this so much easier on windows?..

https://askubuntu.com/questions/843344/share-ethernet-connection-with-second-nic-smarttv according to this it should literally be that simple. But when I click connect after setting this up, these notifications get vomited at me and it immediately disconnects