Why do you need to convert copper (II) hydroxide to copper (II) oxide before converting to copper (II) sulfate?
I would like to add to what Jason has already mentioned:

1.Copper Hydroxide is comparatively tougher to handle since it contains a lot more impurities ( when we are converting Cu(II)nitrate to hydroxide using NaOH, the impurities could be sodium nitrate, excess sodium hydroxide. )


Copper Hydroxide itself is blue, so the equivalence point (when exact amount of copper hydroxide has reacted with concentrated sulphuric acid) of the reaction would be hard to detect, and so yield would drop (since you would again have to neutralise the excess sulphuric acid before purification or conversion to copper metal).
In contrast to this CuO is a black precipitate and can be easily isolated (comparatively) by a Hirsch funnel (or any such equivalent apparatus). This improves the overall yield of further steps and eases the process of purification.


Hope this helps.