If you wish to use your Office 365 Email as an IMAP or POP, check below on how to set it up as IMAP or POP.
Settings for IMAP and POP
Step 1. Open Outlook.
Step 2. Click the File tab.

Step 3. Click +Add Account.

Step 4. Tick the checkbox Let me set up my account manually. Click the Next.

Step 5. From the Choose Service, select IMAP/POP. Click Next.

Step 6. On the POP and IMAP Account Settings screen, fill out the various fields:

Your Name | Enter the identifying name for your email address. In the example, this is My Email, but it can be a functional name like your first name. |
Email Address | Enter the full email address, such as [email protected]. |
Account Type | Choose whether you want to use POP3 or IMAP. |
Incoming Mail Server | outlook.office365.com |
Outgoing Mail Server (SMTP) | outlook.office365.com |
User Name | Enter your full email address, such as [email protected]. |
Password | Enter the password you use for this email address. We recommend checking the Remember Password box so Outlook will save your password for future use. |
Require logon using Secure Password Authentication | Do not check this option. |
Step 7. Click More Settings.
Step 8. Click theOutgoing Server tab, check My outgoing server (SMTP) requires authentication box, and then check Use same settings as my incoming mail server.

Step 9. Click the Advancedtab, under Server Port Numbers change the port numbers to the following:

IMAP | POP | |
Server Ports | Incoming: 993 Outgoing: 587 | Incoming: 995 Outgoing: 587 |
Encryption Method | Incoming: SSL Outgoing: TLS | Incoming: SSL Outgoing: TLS |
Step 10. Click OK, then Next.
Step 11. Outlook will now test your account settings and you’ll see:

Step 12. Click Close, and click Finish.
Now you’re ready to use your Office 365 email with your Outlook desktop application.