I am seeing that many templates are being sold online but I have one question related to it. I downloaded some free templates and tested them out. They are not working, means when I am clicking on home menu or about menu then nothing is happening. I searched for it and learned that the template needs to be coded. So can anyone please tell me how to code a template. I am not a programmer so I don't know anything about coding. Please help me.

it is good to learn template coding but u need to learn some languages first
the basic things u need to know before design any simple templates
- HTML
- CSS
- Basic knowledge of phptoshope

u can learn html and css from http://www.w3schools.com

There are many kind of templates. If you are talking about just PSD templates and you want to code them then you can use the in built Photoshop feauture to export it as a web page. And it will export the Document as a HTML page along with the images that were sliced. Then just open it in Dreamweaver and link them properly.

If you are talking about templates that people are selling for php scripts then they are bit harder to code. You will need understanding of programming language. Plus some syntax and workings of the template engine if one is used. EX: some scripts do use smarty template engine.