For security you might want to disable direct SSH login as root.
First of all login as root and create an user which
useradd sshadmin passwd sshadmin
Now add this user to wheel group from WHM
WHM -> Security Center -> Manage Wheel Group Users
OR from command line
usermod -G wheel sshadmin
Now open /etc/ssh/sshd_config and set
Restart the ssh service
Now you can ssh to server as user sshadmin and run the command “su -” to switch to root user.
Now the thing is that “su -” asks for root password. If you don’t want to remember the root password then you can add the user sshadmin to sudo user list. Add below lines to /etc/sudoers
sshadmin ALL=(ALL) ALL
Now run the command “sudo su -” and it will directly switch to user root without asking password.