Hi Daniela,
Yes to what you said about the unit equivalencies; its
W = P x V (disregarding negative signs right now)
1J = 1kPa x 1L
So to convert from kPa to J, you will need the volume, and you will multiple the volume (in L) to the pressure (in kPa).
I think you are already on the right track. Let me know if you have any more questions! :)
Cheers, and happy studying!