We can have multiple accounts under the Microsoft Outlook and the setting is similar on how the first time you have set email accounts on it.
Below is the guideline for the process to be taken:
Add a Microsoft Exchange account
Emails accounts can be added when you run Outlook for the first time, or by closing Outlook, and then clicking the Mail icon in Control Panel in Windows.
1. Close Outlook.
2. In Control Panel, open the Mail module.
NOTE: The Mail icon in Control Panel will not appear unless you have Outlook installed and have accessed it at leastonce. You can add an Exchange account either to a new profile that you create or to an existing profile.
3. Do one of the following:
Create a new profile
A. Under Profiles, click Show Profiles.
B. Click Add.
C. In the New Profile dialog box, type a name for the profile, and then click OK.
This is the name that you will see when starting Outlook if you configure Outlook to prompt you for a profile to use.
Choose an existing profile
The title bar of the Mail Setup dialog box contains the name of the current profile. To select a different profile, click Show Profiles, select the profile name, and then click Properties.
A. Click E-mail Accounts.
B. Click New.