Installation question and email server suggestions

I am using Digital Ocean droplet with this specs:
2 GB
Ubuntu 18.04 x64
1 vCPU

and i installed erp using the easy install guide and everything went well but i am little bit confused because are the installation i tried to access my public ip and i found the login page perfectly but i saw a post i dont remember exactly where that i should go trough other installation process rather than the setup wizard which are the creating new app and new site guides so my question is are these guides important and essential before i start logging into my erp? or should i stick with the setup wizard and ignore theses guides? and what are theses guides for? i mean why should i make a new app and a new site while everything appear well on my website or do these guides refer to something i dont understand?

i hope someone can help me in this question

and the second thing i would like to ask about is the email servers
i have more then one option but i would definitely prefer a free option or the low cost option because i cannot afford another droplet

i though about these things:

  1. creating an email server on the same droplet
  2. installing a web control panel with email server within the same droplet but under another folder or for example (
  3. using another email hosting services like gmail but that will cost me money which i may not afford or if you know anything that is for free

so what are yours suggestions and is it possible to make #1 or #2 ?

and i am in the production mode if anyone would like to ask and after i installed the bench manager i dont know how to access it and it didnt even show me the port it is installed on?

You can set up the other services on the same machine, as long as you adjust the various ports so that they don’t clash/conflict. For example, to change the port your ERPNext production system is on, do

bench set-nginx-port site1.local 8180
bench setup nginx
sudo systemctl reload nginx

Then you will browse to http://publicIP:8180.

You can set up your own mailserver - I recommend looking at this article, and adapting to your needs…