1. First of all you need to sign into Google calendar and enable the "Holidays in India" calendar. Make sure to use the same gmail email address which you have used in your phone to sign into your gmail app or playstore.
2. Now in your phone, install google calendar from play store and open it.
3. After opening the google calendar, tap on the top left menu to open the sidebar and check what information you want to display in your calendar like Birthdays, Holidays etc.
4. Now open MIUI calendar and from the top right corner, tap on menu and then SETTINGS.
5. Now enable the option "Show Holidays" and then from "Events in Calendar" option, select your preferred email and check the option "Holidays in India".
6. That's it. Now if you open the MIUI calendar, you will be able to see color dots on the holiday dates. If you tap on the date, it will show the holiday details under the agenda.
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