I want to create SMTP Server or Host for sending and receving mail and also send mail from laravel aplication

Need some suggestions or guidelines I want to create a mail server and want to create mail like [email protected], mail2@mydomain.com to sending and receiving mail. The last thing I want to do is sent mail from my Laravel application and for that, I need to config this below thing in Laravel

MAIL_MAILER=smtp
MAIL_HOST=mailhog
MAIL_PORT=1025
MAIL_USERNAME=null
MAIL_PASSWORD=null
MAIL_ENCRYPTION=null
MAIL_FROM_ADDRESS=null
MAIL_FROM_NAME="${APP_NAME}"

I already have 2 droplets in DigitalOcean. one for testing and one for production. I don't want to screw my production droplet (Laravel hosted in the droplet). I will buy another droplet for email hosting. So I need a proper solution or need a suggestion to solve this problem. my domain is https://ghorerrannabd.com/

any third party suggestion will also be great.