What do you want to change on what kind of device? Wi-Fi settings on a Chromecast? If yes, the easiest is probably to do a factory reset on the Chromecast ( https://support.google.com/chromecast/answer/6254654?hl=en ), then set it up again with the Google Home app.
Thanks for the help here, olavrb.
Brandusa, hope that helps. In addition to that, you can also check this support website article to learn more about how to change the Wi-Fi network of Chromecast. Feel free to reach back if you still need help. We're always here for you.