Config mail server on Ubuntu -- 3

I am looking for a freelancer who can help me configure a mail server on my Ubuntu system. I prefer to use Postfix as the mail server software. Additionally, I would like a web-based email client(Roundcube) installed as well. For the security measures, I require standard security measures for my mail server.

Please note that I have several domains. I want to create an email panel for each one on the same server, enabling them to send and receive emails.
For example:
support[@]domain1.com
payment[@]domain1.com
support[@]domain2.com
,...

Important:
We need a bash file to install and configuration all things is need for config mail server and webclient(Roundcube)

Emails sent should not be identified as spam

Get high score in mail-tester.com

Bash file must have comments for each command

Skills and Experience:
- Experience in configuring mail servers on Ubuntu, specifically with Postfix
- Knowledge of web-based email clients and their installation(Roundcube)
- Understanding of standard security measures for mail servers