When using Google Calendar, I personally like the month view (like you would see on a wall calendar); however, that is a matter of preference. To make your calendar go to a full-screen view,, no matter what calendar view you prefer, you can collapse the left-side menu and the right-side panel. Reflected below are instructions to walk you through this:
On the top left side of the screen, click the three-line menu icon at the top to collapse the side menu. You can toggle open the side menu by clicking on the three-line menu.
On the bottom right side, click the small right-facing arrow to collapse the side panel. This panel lets you view your Google Keep Notes, Tasks and other services. You can toggle the side panel back open by clicking the left-facing arrow.