There's no substitute for knowing what you're talking about. Learn about as much as you can both in your role and in the broader setting.

This can make you invaluable, even indispensable.

The purpose is to increase your utility to your work environment for you benefit! To leverage it to get into the role, position, pay & responsibilities you want next.

The employer may decide your utility should benefit them and give you Jobs no one else wants, or give you too much work. This is to be resisted.

They're going to try to use you. Only way to win is use them back harder.