There are two ways that you can access your Google Calendar. The first way is to go to the Google Calendar website at https://calendar.google.com. You will need to be logged in with your Google account in order to access your calendar.
The second way to access your Google Calendar is through the Google Calendar app. This is available for both Android and iOS devices. Once you have installed the app, you will need to sign in with your Google account in order to access your calendar.