You can set up incoming and outgoing email in Odoo Community Edition by following these steps 

https://www.odoo.com/documentation/16.0/administration/maintain/azure_oauth.html

1. As a system admin, go to Settings ‣ General Settings ‣ Discuss in Odoo, and enable the Custom Email Servers option. Then, click Save.
2. Next, click Outgoing Email Servers and click Create to create a new outgoing mail server record in Odoo. Reference the SMTP data of the external email server.
3. To configure incoming mail servers in Odoo, go to Settings > Email > Incoming Mail servers and click on Create. Fill in the required fields such as Server Name, Server Type, Login, Password etc.
4. Once you have set up your incoming and outgoing email servers, you can send invoices by email.

If you have a Microsoft 365 subscription, you can use Outlook to set up your email 

Here are some steps to help you get started:

1 Go to Settings -> General Settings -> Email and configure your SMTP server settings using the SMTP server provided by Microsoft 365.

2 Go to Settings -> Users & Companies -> Users and edit your user. Under the Email tab, fill in your Microsoft 365 email address and password.

3 Test your email settings using the Test Email button in the Email settings.

4 Follow the same steps as above to configure your outgoing email templates and send invoices by email.

Hi,

Here is a detailed video on how to set up and coming and outgoing email servers in odoo.

Please refer this: 

https://www.cybrosys.com/odoo/videos/technical/configure-email-server-in-odoo-16

Regards

Hi, you can follow this:

https://youtu.be/bx8JXli-Y6A

Hope it helps