Passwords can be reset in four ways:
In User Management, in the left pane, click multiple users and then click the password reset button.
This will generate a password reset email for each of the users.
Click into an individual users settings and notice at the bottom, you have additional password reset options:
Send password reset link will act as the batch process above. An email will be sent and the user can take action.
Set password manually will allow you to set a password and provide it to the user.