how can i make a addional root account

i share the server but i must know how to make a second root account

What purpose would a second root account serve?

There is only ONE "su"

I don't od BSD a lot
but try adding in the group "wheel"....
But again, not sure on this

You make make a root account by giving an account the UID of 0. I would not really recomend doing this.

The users you add to the "wheel" group in FreeBSD will have access to the "su" command. If the user is not added to that group and tries to su, he/she will recieve the following message:

su: you are not in the correct group to su root.

so if i add a account to the below group it will be a root account cool...

how must i make a useraccount and add it to group wheel

wheel 10 root