One of the new features added to Windows 10 with the September (1909) update was to enable Calendar users to be able to simply create a Calendar event directly from the Calendar flyout on the Taskbar.
To add quickly and easily add your Calendar event:
– Click on the date and time at the lower right corner of the Taskbar to open the Calendar flyout.
– Pick your desired date and type your text box to identify your event.
– Use the Inline options to set a time and location.