Blogs in Moodle Courses
Bear in mind that Moodle blogs are generally attached to the person. However, there are options for “View all entries about this course” and “Add an entry about this course”. If you’re seeing content from other courses (presumably your blog postings from those courses), make sure you’re using the appropriate link to view the blog.
To add blogs, add a block and select "blog Menu". Then, "Blog" Block will appear on right hand side.