Hi Yunel,

To send and receive mail, you need to configure incoming and outgoing mail in odoo.

Just Refer this:

https://www.odoo.com/documentation/user/12.0/discuss/email_servers.html

After successfully configure, you will see email and messages.

Hope it will useful for you.

Thank you Haresh for the link you provided. I spent several hours searching for an approach that sounds correct and was frustrated to see lot of  pages that describe how to setup a single gmail account as if Odoo is for personal use (although this can work but it is not the proper use case for odoo). The approach provided by your link is however more realistic, simple and most importantly recommended by Odoo.