Question

I want to delete mails from outlook.

Answer 1

With Mail.dll you can delete and manage email on any IMAP or POP3 server (including Exchange).

Outlook is a client application. If you want to delete email from a local pst store, Mail.dll is not going to help you, but if you want to delete emails from Exchange read this post:
https://www.limilabs.com/blog/delete-email-messages-with-imap