#1 Go back and add your location to your profile so someone can help you.
#2 The insulation you have now is up side down.
Vaper barrier goes toward the conditioned surface.
#3 Going to have to seal up any place wires where run through the top plates and around any light or fan penatrations.
#4 Need to add foam or plastic baffles so the new insulation does not cover up the soffit vents.
Blown in would work best.
Buy 10 bags and any of the box stores will let you use the blower for free.