What is an administrator?

 An administrator can add and manage other users, install apps, and change settings. The new user you create when you first set up your Mac is an administrator.

Set up users, guests, and groups on Mac - Apple Support

Hi whatistheproblemnow,

daapple has the correct answer regarding your question.

Just to confirm, do your username and password work as expected when you want to change system settings or install new software?