How do you connect smart keyboard to IPad Pro?

As explained in the Article you came from:

Connect to your iPad Pro

Connect your Smart Keyboard to your iPad Pro with the Smart Connector, which has three small, magnetic contacts. The Smart Connector is on the top edge of your Smart Keyboard and on the side of your iPad Pro.

Unlike Bluetooth keyboards, you don't need to pair or turn on your Smart Keyboard. Just make sure the keyboard is connected and in the Type position to use it.

You connect the iPad to the keyboard with the iPad in a horizontal or Landscape position:

If you are using the iPad in a vertical or upright position also called "Portrait" mode with the camera at the top rather than on the left side, then you cannot use the smart keyboard with it.

You can use a regular unattached bluetooth keyboard instead.

Hi,

Follow the instructions here > Use your Smart Keyboard with iPad Pro - Apple Support