While logged in, click on "My Blog Posts" in the upper left to view all of your blog posts. Find the blog post with the unwanted comment and click on the title to view the entire blog post and scroll down to the bottom to see the comments. Click "Delete" on the unwanted post to remove it permanently.
HiHello my name is Carlos and I like reading and hanging out with friends. So pretty much that's all I gotta say but I still have to write more which total sucks.