You can configure Microsoft 365 MFA account for notification settings if you want Veeam Backup & Replication to send email notifications about backup job results.
You can configure Microsoft 365 non-MFA account for notification settings if you want Veeam Backup & Replication to send email notifications about backup job results.
You can configure the SendGrid account as an SMTP relay for notification settings if you want Veeam Backup & Replication to send email notifications about backup job results.
If you would like to monitor the backup policy result of Veeam backup for Microsoft Azure, the email notification is useful tool to help you to monitor it.
You can follow steps as below to use a free SendGrid account for the email notification at Azure.