depends, If ya want to keep the walnut, Id remove the doors and drawers sand the face frame, stain and use GFs poly finish. It can be brushed on. Then build the doors and drawers stain and finish in the shop , use Euro hinges /hardware.
You could also use a white GF poly or have the poly tinted to what ever color you want. Since you have a HVLP its not that big of a deal to spray in place.