To send email from a Gmail address using a desktop email client like Thunderbird or Outlook, you need to configure Gmail’s SMTP settings. Some email clients do this automatically when you enter your login credentials, but some require manual configuration. This article provides the Gmail SMTP settings you need to send email from your email client of choice. The process is easy, takes less than a minute and requires no technical knowledge. You just need to know the correct settings and where to enter them.
Source: https://sites.google.com/view/set-up-your-gmaiil-smtp-seting/home