How can I connect Smart Keyboard to my I pad mini

The iPad mini is not compatible with Apple’s range of Smart (folio) keyboards. These keyboards are model specific - each being designed to fit the specific dimensions of the iPad model for which it is designed.

Likewise, the iPad mini lacks the “smart connector” that electrically connects the folio keyboard to the iPad.

Instead of an Apple Smart Keyboard, if you look, you may find a third-party folio keyboard that meets you need - that is both self-powered and able connect to your iPad using Bluetooth.