There are no active pens for this model -- so no pressure sensitivity.   If you a touchscreen (OLED), a generic capacitive stylus should work -- but for full active pen support, this is the wrong model system.

Thank you for the reply

What stylus models would be compatible? I'm hoping to use it for handwriting if possible.

If the system is new, there are models that offer what you're looking for.  This model is not suited for handwriting.

The Latitude 7450 2-in-1 or 9450 would be the models to look at.

It is the XPS 14 9440

Yes, I realize that.  That system is not going to be suited for use with handwriting.  My suggestion is that if you're within 30 days of shipment, consider returning this model and replacing it with a true 2-in-1 (the two Latitudes I mention will both offer support for an active pen, for use with handwriting).

Otherwise, if you plan to make do with the model you have, realize that it may work for occasional writing but you won't get the smoothness, precision or pressure sensitivity that's required for extensive writing.  You can use a capacitive stylus, which will give you about the precision you might get from a piece of chalk on a blackboard.

Example:

capacitive stylus