If I change router and wifi password, am I forced to reset all devices like yeelight bulb color and chuangmi camera to have them connected again to my smartphone and mi home/yeelight apps?
Yes of course.
It is a very easy process to change your Wifi password. Visit your wifi homepage and click on settings option and from there you can change it. If you are a new user of Linksys Smart WiFi router and you are getting a problem in creating an account in it or getting problem regarding default password then visit here Linksys Smart WiFi Default Password to get the best solutions of your problem.