Apple Pencil

Verify that your Apple Pencil is compatible with your new iPad:

Apple Pencil compatibility - Apple Support

The first and second generation Pencil use an entirely different pairing and charging interface. The second generation Pencil can only be used with iPad models that have the magnetic/inductive dock that is exclusively designed for the Pencil. Charging is controlled via the iPad magnetic dock.

The first generation Apple Pencil uses the physical Lightning port for both pairing and charging the first generation Pencil. This pencil can only be used with compatible iPad models that have a Lightning connector.

The two models of Apple Pencil are not interchangeable.

Assuming that you have an Apple Pencil that is compatible with your iPad, this support page may be helpful with pairing and use of the Pencil with your iPad:

Connect Apple Pencil with your iPad - Apple Support

If you continue to experience difficulties, here is one of the better troubleshooting guides:

https://appletoolbox.com/apple-pencil-not-working-heres-our-troubleshooting-guide/

You ARE using the correct version of the Pencil with that 2017 iPad Pro model ( model with Home button ).

Prior to this issue, when was the last time your Pencil was charged up and used?

Did your Pencil EVER lay around unused for ANY prolonged period of time without being charged up and ready to use?