In order to subscribe to a blog's feed you need to know the blog's feed URL. A feed is a data format used for providing users with frequently updated content. Content distributors syndicate a web feed, thereby allowing users to subscribe to it. It gives users a way to keep up with many sites on the web without having to visit each site individually to see if they have updated. Some users use their feed to check that their own blog is publishing correctly. The feed url for blog on Blogger is:
http://yourblogname.blogspot.com/atom.xml