How to check Apple Pencil charge on iPad mini 6

Apple Pencil battery charge can be found in Battery Widget in the Today View or on yout home screen's if you have aded the widget to it.

click here ➜ Add, edit, and remove widgets on iPad - Apple Support

The battery status of your paired Apple Pencil is usefully (and always) available from iPad settings:

Settings > Apple Pencil

Optionally, you can add the Battery Widget to any Home Screen or your iPad's Today View. The process of adding Widgets is described within the iPad User Guide:

Add, edit, and remove widgets on iPad - Apple Support