You can choose whether to have notifications for events, and whether you want to get notifications over email or in your browser.
Open Google Calendar on your computer.
In the top right, click Settings Settings and then Settings.
At the top of the page, click the Calendars tab.
Next to your calendar's name, click Edit notifications.
Click Add a notification or edit an existing notification.
At the bottom of the page, click Save.
Note: To get notifications on your computer, you need to have Google Calendar open in your browser.