Magento 2 have that ability to send emails on proper events and actions.
But actually email sending and receiving done by any email services only like Postfix , SMTP etc.
so if you don't wanted to install the extension then you need to configured that services on your server level , so ask your hosting provider to install the Postfix or other email service
then integrate with magento 2 and your email will be worked !!
hope it helps
In Magento 2, Mail isn't sent by SMTP by default, it uses php function mail().
To use SMTP you have to install free extension Gmail SMTP,
Its free and you can download from below github repository,