You can’t disable the entire Notification Center, but you can allow/disallow notifications:
Change Notifications settings on Mac
Allow notifications: Turn notifications on or off. When you turn notifications off, the alert style and other notification options are dimmed.
Use Focus instead
That said, I do not recommend turning off notifications. They are there to alert you to timely/important things. Instead, I highly suggest your configure and enable a/some Focus schedules. I have several configured: Head Down (intensive work), Work (less intensive), and Open. Some are scheduled while others are manually activated. It will silence notifications during that focus time.