You can open the due date picker to set the time, or go to the Daily Planner page and then drag and drop a task onto the right sidebar Calendar to set the start

You can open the due date picker to set the time, or go to the Daily Planner page and then drag and drop a task onto the right sidebar Calendar to set the start and end time. Weekly Planner and Daily Planner are the two main views, so you need to go to these pages to check for due tasks.