Can i add a link to create new post on index page?

Hi folks,
I am trying to create a very minimal posting page that will reside in an iframe on my website’s main page. I want the comments to show one after another but I want my users to be able to make a new post quickly, without having to go to the dashboard. I guess I would like for anyone to be able to write a post similar to how you would leave a comment on an existing one.

Any ideas?