Does the new iPad have a headphone jack?

No.

To connect wires headphones, you’ll either require an appropriate USB-C adapter, or a USB-C hub that includes a headphone jack.

From Apple:

• USB-C to 3.5mm Headphone Jack Adapter

https://store.apple.com/uk/xc/product/MU7E2ZM/A

No.

Sorry.

Apple has abandoned the 3.5mm headphone jack on all of its newer mobile devices and Macbook line up to allow for future thinner and thinner device case designs.

So, its use a Lightning or USB-C to 3.5mm audio jack adapter, now, on all Apple mobile devices for wired audio devices OR purchase and use wireless, Bluetooth AirPods or third party earpods or headphones.

Sorry & Best of Luck to You!