Office 365 Outlook Find POP, IMAP and SMTP Servers

1. go to portal.office.com

2. Open Outlook app

3. Gear Icon | Your app settings | Mail |

4. Expand Tree: Mail | Accounts | POP and IMAP

Normally servers are:

POP setting
Server name: outlook.office365.com
Port: 995
Encryption method: TLS

IMAP setting
Server name: outlook.office365.com
Port: 993
Encryption method: TLS

SMTP setting
Server name: smtp.office365.com
Port: 587
Encryption method: STARTTLS

For more info see : here