For SMTP setup we will use the WP Mail SMTP by WPForms plugin
1- Login to wordpress admin and go to plugins menu
2- Click Add New Plugin
3- Search for “wp mail smtp”, and install the WP mail SMTP by WPForms plugin
4- Click Activate
5- Click lets get Started
6- Choose your preferred SMPT mailer, In this Guide we will set up the smtp server using gmail, choose Google / Gmail and click save and continue.
7- to configure the plugin we need a Client ID and Client Secret. Here is a video guide on how to generate the keys on Google Cloud Console and configure the plugin. https://www.youtube.com/watch?v=m7wd016ARSU