login as superuser

I am trying to find out how to log in as “superuser”, as a program I am trying to install says I have to be a “superuser” to install? thanks for any help:(

You don’t login as su
You just become su

Open a terminal

su -
zypper in 'application-name'

Please read this: https://en.opensuse.org/SDB%3ALogin_as_root