After setting the source file type and the source file directory as well as the schema type Users some options will appear in the navigation bar:
2. Conditions
To get to the setting Users & Teams you either click on the right arrow in the lower bar or on Users & Teams in the navigation bar.

You can always switch between the options by clicking on the arrow buttons or by clicking on the particular option in the navigation bar.
The setting Conditions is already explained for the contact import.
The explanations can be applied to the typical fields of the Users.
Also, there are the Users & Teams settings.