Why would you want to use a permalink instead of just linking to the blog?
One of the benefits of blogging is that you can quickly and easily update your content on a regular basis. And that consistency will be the key to your success.
Blogs organize content by displaying posts in reverse chronological order. If you send someone to a blog’s home page and the blog gets updated with new content, the post you referred to may not be so easy to find.
Permalinks make blog content easy to find
Each individual blog post has a permalink (permanent link), and if you use that, your readers will always end up in the right place.
Here is a brief video that demonstrates how to find the permalink for a blog post.