If the outside of the box does not indicate the presence of the special adapter - this only being necessary for the iPad10 to charge/pair a first generation Apple Pencil - unless you open the box you cannot be certain that the new USB-C/Lightning adapter is present.
New first generation Pencils sourced from Apple should ship with this special adapter in the box along with the Pencil. Some older stock, purchased from retailers, may lack the USB-C to Lightning adapter - and may instead have an older Lightning to Lightning Adapter that looks very similar.
USB-C to Apple Pencil AdapterFor owners of older first generation Pencils, or for “old stock” new Pencils, the new special adapter can be purchased directly from Apple as an accessory.
https://store.apple.com/uk/xc/product/MQLU3ZM/A