Please see the following link. Depending on how you want it set up, you can either have multiple "accounts" under a single profile, or multiple profiles on a machine/user login. This will give you both alternatives and how you can set them up.
https://support.office.com/en-au/article/Switch-to-another-Outlook-e-mail-profile-be3b617f-3f64-43d3-9037-8313b431803c#bm3
To get exactly the functionality you are asking:
- Go to Mail settings as shown in the link.
- Add your profiles (one per email)
- Underneath the add buttons, you should have two radio buttons, select:"Prompt for a profile to be used"
- Click Apply
- Click properties
- In the popup window Click the "E-mail Accounts..." button and go to the "Data Files" tab.
For each account/file:
- Double Click on the line
- go to the security tab
- select "Always prompt for logon credentials.
- Click OK
This will ask you which profile each time you launch outlook, as well as prompting for credentials.