Use the Custom Home page plugin and link to Posts
One of the Plugins available to hosted Micro.Blogs is Custom home page, which replaces your blog home page with text instead of recent posts
.
That led to a question on the Help Forum: Is there any way to have the modified main page and have a menu item for “Blog” that goes to posts?
The answer came from jsonbecker:
Make a custom template called layouts/blog/list.html. Then you can make a page in your custom theme by making a file named content/blog.md…
Lastly, on your main page, you can now link to /blog and that will use the template above.
For more detailed instructions and any follow-up see the Help Forum page.