Depending on the context, there are 3 options to add a place to your trip schedule.
Option 1 - Add from Place Summary Card
In this case, from the list of places you can directly add a place to the schedule by clicking on the add to schedule button in the Place summary card.
Option 2 - Add from Place Details Card
In this case, from the place details card you card by clicking on the schedule button the place can be added.
Option 3 - From Schedule
Places from the Hopper can be moved to schedule by clicking on the "Add to Schedule" button or by dragging & dropping the place into Schedule.