You, as admin, can manage blogs from the admin panel itself.
Admin panel>blog section> click the upper three dots to add a new blog category.
You can define the root category or add the new blogs to existing categories. Once you post a blog you can link the blog in the blog post list and link it to any category defined earlier.
For more info on managing blogs, follow this article: https://support.fatbit.com/en_US/yocoach-admin-user-manual-version-2-3/blog-management