How to use a Smart Keyboard without connect the Ipad on the keyboard??

The iPad Smart (folio) keyboard does not connect with your iPad via Bluetooth, but instead uses the Smart Connector contacts that you’ll find on the back of the iPad.

If you are having difficulties with the connection between iPad and keyboard, remove the Smart (folio) keyboard from your iPad - and carefully/gently clean the smart connector contacts on both the iPad and keyboard with a soft pencil eraser. Ensure that the contacts are dirt and dust free - and all debris from the eraser have been removed - before reconnecting the two.

If you can't connect your iPad to your Magic Keyboard, Smart Keyboard, or Smart Keyboard Folio - Apple Support