So here it is the amazing step of the amazing kindle to add up 5 regional Indian languages, to make the users select their language for the reading of the book. (amazonkindlesupport.xyz)
Now select your language and click on next button, further select the type of keyboard and click on next button. (phoneradar.com)
Once you run this file, from the drop - down menu, select the language from the menu and press OK. (thewindowsclub.com)