Featured image for my theme

Hello there, I am very new to wordpress and do not know very much about it but I have setup a wordpress site recently and I notice my featured images are getting cropped, I want the full image to appear, how do I do that? my website is http://fastdesivideos.info/

If you scroll down and see “Bollywood Movies” for example, the featured images are cropped and middle part of the image shows, how do I change this setting to make it appear full?