@Rascal818
Google Nest does not make it easy to update Wi-Fi settings for Google Nest cameras and doorbells. That's why their first recommendation is to set the network name (SSID) and password on your new router/modem to the same values used on your old router/modem (https://support.google.com/googlenest/answer/9223711). That's what we've done when getting a new router/modem.
If you can't do that, then you do need to do a factory reset on each device. Have you been using the instructions in this Help topic (the ones after the "Restart" instructions)?
https://support.google.com/googlenest/answer/9252162
