How to add Tamil Language

Hi,

I’m new to wordpress! I’m using version 4.5.2, and I could not find “Tamil” language in its General Settings page.

I want to go to build a Tamil website (with user interface and contents, all are in Tamil). So, want to change my wordpress’s pages, buttons, and all elements to Tamil.

How can I do it?

I’ve checked, the following links after online search, but could not find how to use it, and they have not had a help):
https://ta.www.ads-software.com/
https://ta-lk.www.ads-software.com
[above link has verstion 3.3 download, but I need Tamil for current 4.5.2]

Again, I’m completely new to wordpress, so expecting step-by-step procedure, or helpful tutor links.

??