On the calendar there are 3 different views (Day, Week and month) and the view will determine what you see when you go to schedule a meeting.
Day OR Week Views - in both of these views you will click on a specific time in the meetings section labeled. When you click in this section a popup opens up with the date and time already filled in. You are now ready search for and select the contact you are meeting with and enter the remaining details of you meeting.
Month View - In this view you will simply click anywhere inn the box for the date you want and here you will see a small menu open that gives you 3 different choices as shown in the screenshot below.