It's very easy to send emails using Outlook 2019 because you don't need to manually log in to the cPanel webmail.
Here's how you can directly send an email using Outlook 2019,
1. Open Outlook 2019.
2. Under the Home tab, click on New Email.
3. A new window will appear. Fill it in with the following details:
From: If you have multiple email accounts, click on From and choose the correct email account from which you want to send your email.
To Field: Enter the email address of the person to whom you want to send the email.
Subject Field: Enter the subject of your email and your message in the message box.
Write your message in the message box and click on Send.
That's all. You have just sent an email from your Outlook 2019.