Imteaz, first you need to read some of the threads in "help & support". Like, "how to download" "how to seed", stuff like that. "how to download" can also be found at the top of the Bangla Video section. - for quick review, you need to go to each section of which you want to download. For example, for natok, you need to go to Bangla Drama and then click on thread of the natok that you would like to watch. When the thread opens up, you will see a link on the first post (ie. nameofthenatok.avi.torrent), click on that and you are ready to download that is if you have the torrent client installed.

Here is the link that you will need to follow
http://www.banglatorrents.com/bangla-dramas-main/36-how-to-download.html