Every server has a root user that has full privileges to do anything on the server. Being able to do anything is a dangerous ability. In fact, once you've connected your server to ServerPilot, you should try to avoid using SSH or SFTP as root.
You should not upload app files or create files in your app using root. If you do, you'll end up with permissions problems in your apps and your apps won't work correctly.
To upload files to your apps, you should use SSH/SFTP as the serverpilot user or other system users you've created through ServerPilot. For more information, see our system user guide.
If you do need to customize your server, please first search and read our documentation for information that can help.