The SEO ranking will definitely be adversely affected if the material posted is not updated or changed altogether periodically.
Additionally the fresh content will play a major role in the keeping the repeat visits more frequent, as interested subscribers want access to the latest posting on the site.
Learn everything you can and stay on top of your site for success.
Maybe use a company or an App that will improve your chances of getting to page one on Google or other platforms.
More thoughts coming soon.