There are two filters you can alter with conditionals:
generate_body_itemtype – default is “WebPage” and “Blog”.
generate_article_itemtype – default is “CreativeWork”.
Using filters: https://generatepress.com/knowledgebase/filter-list/
Other than that you would need to use custom page templates etc.. to alter/add more.
You can use a plugin like that if you like, but it’s definitely not required.
Hope this helps 🙂