Tamil Typing Using Transliteration

Need to do tamil typing :- using Google Transliteration or any other transliteration tool. For example For the words -"என்ன செய்கிறாய் " , you have to type 'yenna seigiraai' and to use any transliteration tool to convert to tamil and return as a docx. or google docs.

Totally need to type 30 pages . A sample page is attached.