Attach the Apple Pencil to the magnetic connector in the center of the top of the iPad (the side where the volume button is). If you don't see a moment of charging near the top of the screen, make sure Bluetooth is turned on.
When you attach the Apple Pencil(Generation 2) to the iPad, the charging state appears on the screen for a moment. To see how much power Apple Pencil has left while using it, look at the Today view on your iPad. Simply swipe from left to right on the home screen or lock screen.
If you are using your iPad Pro to charge the Apple Pencil(Generation 2) and your car's keyless unlocking device (remote key) is nearby, you may not be able to unlock your car with the remote key due to signal interference. If this happens, you can simply keep the iPad Pro away from the remote key or remove the Apple Pencil from the iPad Pro and store it separately. After the Apple Pencil is charged, all signal interference will be eliminated.