You can use Settings on iCloud.com to change the language and time zone for all the features on iCloud.com. You might want to change the time zone if you travel to a new time zone and want your calendar events to show up at the local time in Calendar on iCloud.com.
Note: Changing the language or time zone on iCloud.com doesn’t change the language or time zone for other websites, your web browser, or other apps on your computer.
Change the language on iCloud.com
In Settings on iCloud.com, click the current language, then choose a new language.
Change the time zone on iCloud.com
In Settings on iCloud.com, click the current time zone below Time Zone / Formats.
Click the map near the place whose time zone you want to use.
The time zone you selected and the name of a city near where you clicked are displayed at the bottom of the map. To pick a different city in the selected time zone, click the city name, then choose a different city.