Which Apple pencils will work with which iPads?

My ~ 4-year old Apple Pencil was working beautifully with my 5th gen iPad Air. The Pad's battery would no longer hold a charge, so I got a new iPad Air - but the fully-charged pencil does not pair with the new iPad Air (11" M-3) Now, I learn there are four varieties of pencils - which one will work with the new (2025) pad?