Hello @Aarthi Madhavan ,
the following documentation "Change your display language and time zone in Microsoft 365 for Business" describes how to change the display language and time zone for all your Microsoft 365 apps and services at the same time.
Change your display language and time zone in Microsoft 365 for Business: https://support.microsoft.com/en-us/topic/change-your-display-language-and-time-zone-in-microsoft-365-for-business-6f238bff-5252-441e-b32b-655d5d85d15b
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