What is the most efficient way to set up inbound and out bound email on digitalOcean

What is the most efficient way to setup inbound and outbound email for a wordpress website on digitalOcean. I am sorry but my biggest complaint is following install docs that don’t work and having followed “How To Configure a Mail Server Using Postfix, Dovecot, MySQL, and SpamAssassin” I am again wondering why I am still trying to work out all of the install issues. it just seems like information to get all of the systems up and running are incomplete or poorly written so I end up with errors where there is no notation about how to correct the error. also I have read in some document that the email ports aren’t open to begin with so if that is true how do I get confirmations from the site to my customers. There has to be a way to do this and this is just the tip of the iceberg for me. I also need to align video and music capabilities and am already isolating mysql services to separate droplets so when I go live if growth is what I anticipate the systems in place will be able to grow along with the customer base. but I need help getting email working and have limited funds to put into this to make the primary version of the system work. anything anyone can offer would be greatly appreciated. someone please set me straight as to the best way to get operational on digitalOcean.