difference between the 1st generation pencil with usb-c adaptor and lightening charger

Because the 1st gen Apple Pencil uses the Lightning port to charge, you need to use the USB-C to Apple Pencil adapter to charge it on your 9th Gen iPad which has a USB-C port on it.

If you do NOT own the 1st gen Apple Pencil:

Buy Apple Pencil - Apple

The 1st gen Apple pencil (if purchased new) should include the required adapter in the box.

If you already own the 1st gen Apple Pencil and do NOT have the adapter, you would need to purchase the required adapter to charge the 1st gen Apple Pencil.

USB-C to Apple Pencil Adapter - Apple

Your iPad9 has a Lightning connector - as does a first generation Apple Pencil.

A first generation Apple Pencil is paired with - and can be quickly charged by - the iPad9 by connecting the Pencil directly to the iPad’s Lightning port.

You can also charge the Pencil from your iPad Power Adapter, but to do so you’ll need to use the iPad charging cable and an appropriate adapter. For all models of iPad with a Lightning port, you will require a special Lightning to Lightning Adapter - this being supplied within the box of older first generation Apple Pencils.

The iPad10, by contrast, has a USB-C charging port to which the Pencil must still be connected to pair and charge from the iPad10. For this application you will require a special Lightning to USB-C adapter with which to connect the Pencil to the iPad via the iPad’s charging cable. This adapter is supplied with newer first generation Apple Pencil’s.

The two different Adapters externally look very similar - but fundamentally differ.

You are very welcome.