Can one include the device in one's own product for free?

There seems to be some IPs not free.

Should one pay fee for the IPs, when include the device in one's own product?

Thank you.

What IP you mean?

If you think Nios II f that is included images in Arduino IDE and examples. Used IP:s in these images are included to full Quartus suite that Arduino is using while generating these images.

If you plan to use separated IP from catalog then you need full Quartus license that has IP library included.