Yes you can – that is the beauty of a WordPress Website. You just log in and write post articles for your Blog, edit pages (though this may require some WordPress Training if it has been done with ‘page builders’), and so on.
WordPress is a CMS (Content Management System) that means you log and make these changes. We build the website for you, and hand it over to you. But we can provide monthly WordPress support to do this for you if you prefer.