Administrator is the leading role of a WordPress website. When you install WordPress on your domain, it will automatically create a user, with a username and password during the installation process. The user is assigned the role of administrator and provides complete access to the system. This means you can change and modify your theme, add and install plugins and anything else you want or need to do, to get your site up and running.
An administrator has the ability to add or remove other users from the system, even if they also have administrator status. If you are considering giving another user administrator status, keep in mind that they have the same power as you, and can add, delete or change content and settings as they see fit.
The admin is the only WordPress user role that has the ability to upgrade the core WordPress version. They have the ability to change themes as well as edit the theme files easily by using the built-in theme editor that comes with WordPress. They can also modify, change, add or delete plugins.
If you are managing a multisite installation, several of the capabilities of the admin are granted to a “super admin”. This super admin has the ability to add users, remove and add plugins, change or modify themes and monitor and control the entire network, whereas a standard administrator only manages a single site.