If you have a domain yourdomain.com, your server’s host would be something like server01.yourdomain.com. This what you would use for logging into your root account, while you would be able to run your website at yourdomain.com.

If you want to change Plesk mailbox directories please review this technical article for guidance.

CREATE DIRECTORIES
mkdir -p /home/var/mail
rsync -avz /var/mail /home/var/mail

Connect to the server using SSH/RDP.
Find what SMTP and IMAP/POP3 servers are in use:

# /usr/local/psa/admin/bin/mailmng --features | egrep 'SMTP_Server|IMAP_POP3_Server'
$features['SMTP_Server'] = "Postfix";
$features['IMAP_POP3_Server'] = "Dovecot"; $features['SMTP_Server_package'] = "postfix"; $features['IMAP_POP3_Server_package'] = "dovecot";

Stop the SMTP service:

# service postfix stop
Open the file /etc/psa/psa.conf and change the PLESK_MAILNAMES_D variable:
specify a new location for mailbox directory so that it is like:

# grep PLESK_MAILNAMES_D /etc/psa/psa.conf PLESK_MAILNAMES_D <new_mailnames_directory>

Note: To avoid performance degradation, the new location for the mailboxes directory should be located in the local file system - it should not be mounted as a network share, such as NFS.

Move mailboxes from the current directory to the new location with the
command:

# cp -ap /var/qmail/mailnames/* <new-mailnames-directory> If dovecot is in use, set the new location in the file /etc/dovecot/dovecot.conf by modifying values in the lines below:

# egrep 'mail_home|mail_location' /etc/dovecot/dovecot.conf mail_home = <new_mailnames_directory>/%Ld/%Ln mail_location = maildir:<new_mailnames_directory>/%Ld/%Ln/Maildir
Restart the dovecot service:

# service dovecot restart
After all the steps are done, start SMTP service and reconfigure mail settings using the mchk utility:

# service postfix start
# plesk repair mail
Before creating new mailboxes on new domains configure SELinux in the following way:
following is not required for selinux disabled server.
# chcon -R -t mail_spool_t <new_mailnames_directory>

reference: https://support.plesk.com/hc/en-us/articles/213374889-How-to-change-the-default-location-of-mailboxes-in-Plesk-for-Linux-

IF you want to change virtual hosts location in plesk for linux. Please check below article for assistance.

CHANGING PLESK VHOSTS DIRECTORY FROM /var/www TO /home/var/www

CREATE DIRECTORIES

mkdir -p /home/var/www

rsync -avz /var/www /home/var/www
/usr/local/psa/bin/transvhosts.pl --dest-dir /home/var/www --correct-scripts

reference: https://support.plesk.com/hc/en-us/articles/213367009-How-to-change-virtual-hosts-location-in-Plesk-for-Linux

Unlike normal hosting plans, which put many customers' accounts on a single server, a Dedicated Server is reserved exclusively for the account and usage of a single customer. This means that the Dedicated Server customer has exclusive rights to their server's bandwidth, memory, and storage space, and performance is not affected by traffic and the usage patterns of other customers.

When you purchase a Dedicated Server, you are actually leasing a server box that is configured and set up according to your preferences, but remains at our data center. A Dedicated Server account provides you with a dedicated IP address and full control of server usage and software installation, with admin (root) access to the server.

You can use a Dedicated Server for a wide variety of purposes, including gaming servers, database management, and traffic-intensive websites. Dedicated Servers are particularly useful for companies and individuals who run high-traffic websites or applications and who need the bandwidth, versatility, and consistent performance of a dedicated box.

A dedicated hosting service, dedicated server, or is a type of internet hosting in which the client leases an entire server not shared with anyone else. This is more flexible than shared hosting, as organizations have full control over the server(s), including choice of operating system and hardware, etc.