The Apple Pencil (1st gen) can be used on the following devices: iPad Pro, iPad (6th gen), or iPad Air (3rd gen).
For fast charging, plug your Apple Pencil into the Lightning connector on your iPad. If the battery runs out, you can charge it from your iPad for 15 seconds and get 30 minutes of use.
You can also plug your Apple Pencil into a USB port with the Apple Pencil Charging Adapter and a Lightning to USB cable. (not provided by SLUH)
Battery Life of Your Pencil
To see how much charge your Apple Pencil has left, check the Widgets view on your iPad Pro. The Apple Pencil is displayed under the Batteries widget.
If the tops on your Apple Pencil start to wear, you may replace them by purchasing a 4-pack from the Apple web site.
Tutorials from Apple:
Create an instant note from the Lock Screen
With a specified iPad above and an Apple Pencil, you can create an instant note from the Lock screen or pick up where you left off on your last note. To change these settings, go to Settings > Notes, tap Access Notes from the Lock Screen, and choose an option.
Tap the Lock Screen with your Apple Pencil and create your note. Whatever you create is automatically saved in Notes.