Owners of the second-generation Apple Pencil have it easy.
To check the battery, magnetically attach the Apple Pencil to the side of your iPad.
The status only appears briefly, though, and doesn’t help owners of the first-generation Apple Pencil.

This method requires iPadOS 13 or newer.
Swipe right from the Home screen to open Today View.
Scroll to the bottom of Today View and tap theEditbutton.

Tap the+button at the top of Today View.
A menu with a selection of widgets will appear.
Find and tap the Batteries widget.

The next menu will give you several options for the widget.
Choose the one you’d like to use and then tapAdd Widget.
The widget will now appear in Today View.

you might reference it whenever you want to check your Apple Pencil’s battery.
Is There a Battery in the Apple Pencil?
Yes, there is a battery in the Apple Pencil.

To be more specific, the Apple Pencil has a built-in rechargeable lithium-ion battery.
It’s no different from your phone or laptop, but much smaller.
This is a bit different from the Apple Pencil’s competitors, like the Microsoft Surface Pen.
Many have a replaceable, disposable battery, such as a AAAA battery or a watch battery.
It’s not possible to replace the Apple Pencil’s battery.
The Pencil must be replaced if the battery fails.
FAQ
A fully charged Apple Pencil should last you about 12 hours.
If your battery is dead, charging for about 15 seconds can get you around 30 minutes of use.
If the Pencil won’t pair this way, go intoSettings>Bluetoothand check that Bluetooth is turned on.
Tap on the Pencil, then tap theinfo button>Forget.
Connect your Pencil to the iPad again and tap on the Pair button.