If you want to delete a comment, first make sure that you are logged in to the correct Blogger account (administrator of the blog or author of the comment). Then go to the blog and find the page where the comment is listed. Next to the comment, you should see a trash can icon, like this:

Now Click on the trash icon can and you will see this confirmation page, which also lists the comment for review:

You can click cancel, if you don't want to delete comment. Clicking the "Delete Comment" button will remove the text of the comment from your page, but leave the author's name and a message saying "this comment has been removed." If you check the "Remove Forever" option, then no trace of the comment will remain on your blog.