I'm sorry, put this where it needs to go, I've added a user in plesk, he has his own domain name.

How do I give him shell access to var/www/vhosts/hisdomain.com so he can get into hlds and run an instance of that? I've set it up for him from root, but obviously I don't want to give that to him, I tried to login with his plesk username, but it kicks me right out.

Is there some fancy way to do this? and to mods, I apologize, if this should go in the linux forum, take me there, I have no idea.

I have created a user with useradd username123 and made his password with passwd, and that gave him root access.

so far linux has shown limitless possibilities, i know it can do this!

There is a plesk opttion to allow the user shell access.

Domains -> click the domain -> "Shell access to server with FTP user's credentials"

That is true, and here are my options:

Forbidden

/bin/sh
/bin/bash
sbin more bins


none of them list out /var/www/vhosts their domain, I only want them access to their domain directory, and can't go changing or doing anything else with the entire server.

those are shell types... Normally Linux users would be used to /bin/bash.

eg:
[root@basic ~]# adduser shuser -s /bin/sh
[root@basic ~]# env | grep SHELL
SHELL=/bin/bash
[root@basic ~]# su -l shuser
-sh-3.1$ env | grep SHELL
SHELL=/bin/sh
-sh-3.1$