@Smalltimore
Google Nest generally doesn't make it easy to change Wi-Fi settings. In fact, they say: "The simplest fix for most Nest products is to update your home network so that the network name (SSID) and password are the same as before." (https://support.google.com/googlenest/answer/9223711?hl=en#zippy=%2Ctry-the-same-network-name-and-pa...). When we got a new router/modem, we set the network name (SSID) and password to the same values used on the old router/modem, and did not have to update any of our Google Nest devices.
If you can't do that, then the Google Nest process calls for removing the Google Nest device(s) from the Google Nest app or the Google Home app while you are still on the old Wi-Fi network, then doing a factory reset, and then reinstalling on the new Wi-Fi network. If you fail to remove the device while you are still on your old Wi-Fi network, you can encounter issues you cannot resolve (like messages saying the device is connected to another account [yours!]).
If you can't resolve it, you may need to contact Support (https://support.google.com/googlenest/gethelp) to see if you can get someone knowledgeable who can override the controls Google Nest imposes.
